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Chatbots Seem More Empathetic Than Docs in Cancer Discussions
Large language models (LLM) such as ChatGPT have shown mixed results in the quality of their responses to consumer questions about cancer.
One recent study found AI chatbots to churn out incomplete, inaccurate, or even nonsensical cancer treatment recommendations, while another found them to generate largely accurate — if technical — responses to the most common cancer questions.
While researchers have seen success with purpose-built chatbots created to address patient concerns about specific cancers, the consensus to date has been that the generalized models like ChatGPT remain works in progress and that physicians should avoid pointing patients to them, for now.
Yet new findings suggest that these chatbots may do better than individual physicians, at least on some measures, when it comes to answering queries about cancer. For research published May 16 in JAMA Oncology (doi: 10.1001/jamaoncol.2024.0836), David Chen, a medical student at the University of Toronto, and his colleagues, isolated a random sample of 200 questions related to cancer care addressed to doctors on the public online forum Reddit. They then compared responses from oncologists with responses generated by three different AI chatbots. The blinded responses were rated for quality, readability, and empathy by six physicians, including oncologists and palliative and supportive care specialists.
Mr. Chen and colleagues’ research was modeled after a 2023 study that measured the quality of physician responses compared with chatbots for general medicine questions addressed to doctors on Reddit. That study found that the chatbots produced more empathetic-sounding answers, something Mr. Chen’s study also found. : quality, empathy, and readability.
Q&A With Author of New Research
Mr. Chen discussed his new study’s implications during an interview with this news organization.
Question: What is novel about this study?
Mr. Chen: We’ve seen many evaluations of chatbots that test for medical accuracy, but this study occurs in the domain of oncology care, where there are unique psychosocial and emotional considerations that are not precisely reflected in a general medicine setting. In effect, this study is putting these chatbots through a harder challenge.
Question: Why would chatbot responses seem more empathetic than those of physicians?
Mr. Chen: With the physician responses that we observed in our sample data set, we saw that there was very high variation of amount of apparent effort [in the physician responses]. Some physicians would put in a lot of time and effort, thinking through their response, and others wouldn’t do so as much. These chatbots don’t face fatigue the way humans do, or burnout. So they’re able to consistently provide responses with less variation in empathy.
Question: Do chatbots just seem empathetic because they are chattier?
Mr. Chen: We did think of verbosity as a potential confounder in this study. So we set a word count limit for the chatbot responses to keep it in the range of the physician responses. That way, verbosity was no longer a significant factor.
Question: How were quality and empathy measured by the reviewers?
Mr. Chen: For our study we used two teams of readers, each team composed of three physicians. In terms of the actual metrics we used, they were pilot metrics. There are no well-defined measurement scales or checklists that we could use to measure empathy. This is an emerging field of research. So we came up by consensus with our own set of ratings, and we feel that this is an area for the research to define a standardized set of guidelines.
Another novel aspect of this study is that we separated out different dimensions of quality and empathy. A quality response didn’t just mean it was medically accurate — quality also had to do with the focus and completeness of the response.
With empathy there are cognitive and emotional dimensions. Cognitive empathy uses critical thinking to understand the person’s emotions and thoughts and then adjusting a response to fit that. A patient may not want the best medically indicated treatment for their condition, because they want to preserve their quality of life. The chatbot may be able to adjust its recommendation with consideration of some of those humanistic elements that the patient is presenting with.
Emotional empathy is more about being supportive of the patient’s emotions by using expressions like ‘I understand where you’re coming from.’ or, ‘I can see how that makes you feel.’
Question: Why would physicians, not patients, be the best evaluators of empathy?
Mr. Chen: We’re actually very interested in evaluating patient ratings of empathy. We are conducting a follow-up study that evaluates patient ratings of empathy to the same set of chatbot and physician responses,to see if there are differences.
Question: Should cancer patients go ahead and consult chatbots?
Mr. Chen: Although we did observe increases in all of the metrics compared with physicians, this is a very specialized evaluation scenario where we’re using these Reddit questions and responses.
Naturally, we would need to do a trial, a head to head randomized comparison of physicians versus chatbots.
This pilot study does highlight the promising potential of these chatbots to suggest responses. But we can’t fully recommend that they should be used as standalone clinical tools without physicians.
This Q&A was edited for clarity.
Large language models (LLM) such as ChatGPT have shown mixed results in the quality of their responses to consumer questions about cancer.
One recent study found AI chatbots to churn out incomplete, inaccurate, or even nonsensical cancer treatment recommendations, while another found them to generate largely accurate — if technical — responses to the most common cancer questions.
While researchers have seen success with purpose-built chatbots created to address patient concerns about specific cancers, the consensus to date has been that the generalized models like ChatGPT remain works in progress and that physicians should avoid pointing patients to them, for now.
Yet new findings suggest that these chatbots may do better than individual physicians, at least on some measures, when it comes to answering queries about cancer. For research published May 16 in JAMA Oncology (doi: 10.1001/jamaoncol.2024.0836), David Chen, a medical student at the University of Toronto, and his colleagues, isolated a random sample of 200 questions related to cancer care addressed to doctors on the public online forum Reddit. They then compared responses from oncologists with responses generated by three different AI chatbots. The blinded responses were rated for quality, readability, and empathy by six physicians, including oncologists and palliative and supportive care specialists.
Mr. Chen and colleagues’ research was modeled after a 2023 study that measured the quality of physician responses compared with chatbots for general medicine questions addressed to doctors on Reddit. That study found that the chatbots produced more empathetic-sounding answers, something Mr. Chen’s study also found. : quality, empathy, and readability.
Q&A With Author of New Research
Mr. Chen discussed his new study’s implications during an interview with this news organization.
Question: What is novel about this study?
Mr. Chen: We’ve seen many evaluations of chatbots that test for medical accuracy, but this study occurs in the domain of oncology care, where there are unique psychosocial and emotional considerations that are not precisely reflected in a general medicine setting. In effect, this study is putting these chatbots through a harder challenge.
Question: Why would chatbot responses seem more empathetic than those of physicians?
Mr. Chen: With the physician responses that we observed in our sample data set, we saw that there was very high variation of amount of apparent effort [in the physician responses]. Some physicians would put in a lot of time and effort, thinking through their response, and others wouldn’t do so as much. These chatbots don’t face fatigue the way humans do, or burnout. So they’re able to consistently provide responses with less variation in empathy.
Question: Do chatbots just seem empathetic because they are chattier?
Mr. Chen: We did think of verbosity as a potential confounder in this study. So we set a word count limit for the chatbot responses to keep it in the range of the physician responses. That way, verbosity was no longer a significant factor.
Question: How were quality and empathy measured by the reviewers?
Mr. Chen: For our study we used two teams of readers, each team composed of three physicians. In terms of the actual metrics we used, they were pilot metrics. There are no well-defined measurement scales or checklists that we could use to measure empathy. This is an emerging field of research. So we came up by consensus with our own set of ratings, and we feel that this is an area for the research to define a standardized set of guidelines.
Another novel aspect of this study is that we separated out different dimensions of quality and empathy. A quality response didn’t just mean it was medically accurate — quality also had to do with the focus and completeness of the response.
With empathy there are cognitive and emotional dimensions. Cognitive empathy uses critical thinking to understand the person’s emotions and thoughts and then adjusting a response to fit that. A patient may not want the best medically indicated treatment for their condition, because they want to preserve their quality of life. The chatbot may be able to adjust its recommendation with consideration of some of those humanistic elements that the patient is presenting with.
Emotional empathy is more about being supportive of the patient’s emotions by using expressions like ‘I understand where you’re coming from.’ or, ‘I can see how that makes you feel.’
Question: Why would physicians, not patients, be the best evaluators of empathy?
Mr. Chen: We’re actually very interested in evaluating patient ratings of empathy. We are conducting a follow-up study that evaluates patient ratings of empathy to the same set of chatbot and physician responses,to see if there are differences.
Question: Should cancer patients go ahead and consult chatbots?
Mr. Chen: Although we did observe increases in all of the metrics compared with physicians, this is a very specialized evaluation scenario where we’re using these Reddit questions and responses.
Naturally, we would need to do a trial, a head to head randomized comparison of physicians versus chatbots.
This pilot study does highlight the promising potential of these chatbots to suggest responses. But we can’t fully recommend that they should be used as standalone clinical tools without physicians.
This Q&A was edited for clarity.
Large language models (LLM) such as ChatGPT have shown mixed results in the quality of their responses to consumer questions about cancer.
One recent study found AI chatbots to churn out incomplete, inaccurate, or even nonsensical cancer treatment recommendations, while another found them to generate largely accurate — if technical — responses to the most common cancer questions.
While researchers have seen success with purpose-built chatbots created to address patient concerns about specific cancers, the consensus to date has been that the generalized models like ChatGPT remain works in progress and that physicians should avoid pointing patients to them, for now.
Yet new findings suggest that these chatbots may do better than individual physicians, at least on some measures, when it comes to answering queries about cancer. For research published May 16 in JAMA Oncology (doi: 10.1001/jamaoncol.2024.0836), David Chen, a medical student at the University of Toronto, and his colleagues, isolated a random sample of 200 questions related to cancer care addressed to doctors on the public online forum Reddit. They then compared responses from oncologists with responses generated by three different AI chatbots. The blinded responses were rated for quality, readability, and empathy by six physicians, including oncologists and palliative and supportive care specialists.
Mr. Chen and colleagues’ research was modeled after a 2023 study that measured the quality of physician responses compared with chatbots for general medicine questions addressed to doctors on Reddit. That study found that the chatbots produced more empathetic-sounding answers, something Mr. Chen’s study also found. : quality, empathy, and readability.
Q&A With Author of New Research
Mr. Chen discussed his new study’s implications during an interview with this news organization.
Question: What is novel about this study?
Mr. Chen: We’ve seen many evaluations of chatbots that test for medical accuracy, but this study occurs in the domain of oncology care, where there are unique psychosocial and emotional considerations that are not precisely reflected in a general medicine setting. In effect, this study is putting these chatbots through a harder challenge.
Question: Why would chatbot responses seem more empathetic than those of physicians?
Mr. Chen: With the physician responses that we observed in our sample data set, we saw that there was very high variation of amount of apparent effort [in the physician responses]. Some physicians would put in a lot of time and effort, thinking through their response, and others wouldn’t do so as much. These chatbots don’t face fatigue the way humans do, or burnout. So they’re able to consistently provide responses with less variation in empathy.
Question: Do chatbots just seem empathetic because they are chattier?
Mr. Chen: We did think of verbosity as a potential confounder in this study. So we set a word count limit for the chatbot responses to keep it in the range of the physician responses. That way, verbosity was no longer a significant factor.
Question: How were quality and empathy measured by the reviewers?
Mr. Chen: For our study we used two teams of readers, each team composed of three physicians. In terms of the actual metrics we used, they were pilot metrics. There are no well-defined measurement scales or checklists that we could use to measure empathy. This is an emerging field of research. So we came up by consensus with our own set of ratings, and we feel that this is an area for the research to define a standardized set of guidelines.
Another novel aspect of this study is that we separated out different dimensions of quality and empathy. A quality response didn’t just mean it was medically accurate — quality also had to do with the focus and completeness of the response.
With empathy there are cognitive and emotional dimensions. Cognitive empathy uses critical thinking to understand the person’s emotions and thoughts and then adjusting a response to fit that. A patient may not want the best medically indicated treatment for their condition, because they want to preserve their quality of life. The chatbot may be able to adjust its recommendation with consideration of some of those humanistic elements that the patient is presenting with.
Emotional empathy is more about being supportive of the patient’s emotions by using expressions like ‘I understand where you’re coming from.’ or, ‘I can see how that makes you feel.’
Question: Why would physicians, not patients, be the best evaluators of empathy?
Mr. Chen: We’re actually very interested in evaluating patient ratings of empathy. We are conducting a follow-up study that evaluates patient ratings of empathy to the same set of chatbot and physician responses,to see if there are differences.
Question: Should cancer patients go ahead and consult chatbots?
Mr. Chen: Although we did observe increases in all of the metrics compared with physicians, this is a very specialized evaluation scenario where we’re using these Reddit questions and responses.
Naturally, we would need to do a trial, a head to head randomized comparison of physicians versus chatbots.
This pilot study does highlight the promising potential of these chatbots to suggest responses. But we can’t fully recommend that they should be used as standalone clinical tools without physicians.
This Q&A was edited for clarity.
FROM JAMA ONCOLOGY
Outside the Guidelines: Prostate Cancer Screening Overused in Older Men
In its most recent guidance, the US Preventive Services Task Force (USPSTF) revised a previous 2012 recommendation against routine screening for prostate cancer to instead endorse individual decision-making for men aged 55 to 69 years (grade C).
In the update guidance, which was published in 2018, the task force still recommended against PSA-based screening for prostate cancer in men 70 years and older (grade D) due to a range of potential risks and harms. Guidelines from the American Urological Association and American Cancer Society have echoed that recommendation, in general agreement that men over the age of 70 or with limited life expectancy show little benefit from the screening.
To take a closer look at how commonly men are being screened for prostate cancer, based not only on their age but their estimated life expectancy, Kevin H. Kensler, ScD, of Weill Cornell Medicine, and colleagues conducted a cross-sectional study using data from the 2020 Behavioral Risk Factor Surveillance System (BRFSS).
“Our findings indicate that many males aged 70 years and older or those with a high risk of death within 10 years undergo prostate cancer screening despite the recommendation against screening in these populations by current guidelines,” the authors wrote in their paper, published in JAMA Network Open. The results underscore that “enhancements to the shared decision-making process are needed to ensure that older males who undergo screening are those who may potentially benefit,” they noted.
For the study, the authors identified 57,397 men aged 60 and older without a history of prostate cancer who reported undergoing a screening PSA test in the prior 2 years.
Using a risk factor system, mortality risk was estimated based on the scales ranging from 5.5 or less to 10.0 or greater, corresponding to the estimated 10-year mortality of less than 30% to 71% or more, respectively.
Of the men, 19.2% were aged 70 to 74 years, 13.0% were aged 75 to 79 years, and 12.3% were aged 80 years or older. The rest were 69 years or younger.
While the estimated 2-year prostate cancer screening rates were 36.3% among those aged 60 to 64 years and 42.8% for those 65 to 69 years, the rates were even higher, at 47.1%, among those aged 70 to 74 years, and similar, at 42.7%, in the 75 to 79 years of age range. Among those aged 80 years and older, 30.4% had been screened.
While the screening frequency was 43.4% among males with the greatest estimated life expectancy, a fair percentage of men, 30.4%, with the lowest life expectancy, indicative of a 71% or greater risk of death within 10 years, received prostate cancer screening.
In fact, among those with lowest life expectancy, the screening rates were greater than 20% in all age groups.
Screening in Older Age: Benefit in Reducing Mortality Low
Autopsy research indicates that, in fact, as many as 50% of men do have prostate cancer at age 80; however, many of those tumors are low-risk and unlikely to affect the health of the men.
If detected early, as is the intention of screening, prostate cancer can take years to advance and the likelihood of receiving any mortality benefit from continued screening in older age is low.
Furthermore, screening in older age can have implications, including a higher risk of complications following a false positive prostate biopsy that may not have been necessary in the first place, the authors explained.
“Given the long natural history of prostate cancer and lead time associated with PSA-based screening, these males [aged 70 and older or with a high risk of death within 10 years] have a low likelihood of receiving any mortality benefit from continued screening,” the authors reported.
“Yet they face the potential harms of overdiagnosis, such as complications after prostate biopsy for a false-positive screening and psychological stress associated with a cancer diagnosis.”
Guideline Confusion, Habit, Among Reasons for Continued Screening
Among key reasons for the continued screening of men well into old age is the fluctuating history of the guidelines, Dr. Kensler said in an interview.
“There has been considerable variation in prostate cancer screening guidelines over time and across organizations that make screening recommendations, and this has inevitably led to some confusion among clinicians,” he explained.
However, the evidence of a lack of benefit over the age of 70 is strong enough that not performing PSA-based screening among men ages 70 or older is a Healthcare Effectiveness Data and Information Set (HEDIS) measure for quality of care, he noted.
Nevertheless, “I think the trends we found in our analysis reflect that it is difficult for patients and providers to stop providing screening once they have already started it,” Dr. Kensler said.
Another motivator may be an inclination by clinicians to err on the side of caution, he added.
“For clinicians, although they may be aware of the guidelines, they may perhaps fear that they will not have offered screening to one of the older individuals who would have benefited from it even though they recognize that most would not,” Dr. Kensler noted.
Too often, however, such screenings “can lead to a cascade of other events that end up harming the patient without extending their lifespan,” he said.
Difficult Discussions
Complicating matters is the task of informing patients that due to their life expectancy, screening is considered to not likely be worthwhile — which may not be an easy discussion.
“For patients, hearing that they are at a stage of life where they may not benefit from screening is an unpleasant message to receive,” Dr. Kensler said.
“Having an in-depth conversation on this topic is also difficult given the many other health topics that clinicians and patients must cover during a visit.”
Ultimately, “these and other factors lead to inertia, where it is easier to stick to the status quo of continuing screening.”
The challenges underscore the need for improvements to the shared decision-making process to make sure that older men who do undergo prostrate screening will benefit, Dr. Kensler argued.
“If the guidelines are going to recommend shared decision-making, we need to provide tools to help patients and clinicians navigate these potentially difficult conversations.
Life Expectancy Uncertainties
Commenting on the research in an interview, Kyle Richards, MD, associate professor with the Department of Urology at the University of Wisconsin School of Medicine and Public Health, in Madison, noted that, “while most urology experts agree that we should not screen for prostate cancer in men with less than 5-10 years life expectancy, the challenge is deciding which patients have a more limited life expectancy.”
Tools and calculators are available to try to calculate life expectancy, “but they can be cumbersome and difficult to incorporate into clinical practice,” he added.
Indeed, the difficulty in accurately estimating life expectancy is also a limitation of the study, he noted.
“The challenge with a study like this is it is very difficult to accurately estimate life expectancy,” he said. “It is easy to pick a cut point (i.e. age 70) but it is very difficult to calculate one’s life expectancy from survey data alone.”
Another limitation is that “screening PSA testing implies that the patient is not having any symptoms, and we do not know from this study if any of these men were getting PSA checks due to some urinary symptoms or other issues,” Dr. Richards added.
“So, while the study does raise some concern about screening PSA in older men, the data source makes it quite difficult to home in on this question.”
When it can be estimated, life expectancy can indeed provide a more useful guide in assessing the options if a patient is found to have prostate cancer, Dr. Richards noted.
“If a patient has a 5- to 10-year life expectancy, and they are diagnosed with a clinically significant prostate cancer, they absolutely may still benefit from treatment,” he said.
“If they have a clinically significant prostate cancer that is unrecognized, it could metastasize and cause symptoms or lead to death, as roughly 30,000 men die from prostate cancer each year in the USA.”
However, “if a patient has a limited life expectancy of less than 5 to 10 years, don’t screen for prostate cancer,” he advised. Proper guidance should furthermore be made loud and clear in guideline recommendations.
“I do think the USPSTF and AUA need to be the primary voices educating primary care and patients regarding prostate cancer screening,” Dr. Richards said.
“We need to be smart about whom to screen, when to screen, and how often to screen. And this message needs to be heard by the primary care providers that perform the screening.”
The study was supported by the Sandra and Edward Meyer Cancer Center and a grant from the National Cancer Institute of the National Institutes of Health.
Dr. Kensler and Dr. Richards had no disclosures to report.
In its most recent guidance, the US Preventive Services Task Force (USPSTF) revised a previous 2012 recommendation against routine screening for prostate cancer to instead endorse individual decision-making for men aged 55 to 69 years (grade C).
In the update guidance, which was published in 2018, the task force still recommended against PSA-based screening for prostate cancer in men 70 years and older (grade D) due to a range of potential risks and harms. Guidelines from the American Urological Association and American Cancer Society have echoed that recommendation, in general agreement that men over the age of 70 or with limited life expectancy show little benefit from the screening.
To take a closer look at how commonly men are being screened for prostate cancer, based not only on their age but their estimated life expectancy, Kevin H. Kensler, ScD, of Weill Cornell Medicine, and colleagues conducted a cross-sectional study using data from the 2020 Behavioral Risk Factor Surveillance System (BRFSS).
“Our findings indicate that many males aged 70 years and older or those with a high risk of death within 10 years undergo prostate cancer screening despite the recommendation against screening in these populations by current guidelines,” the authors wrote in their paper, published in JAMA Network Open. The results underscore that “enhancements to the shared decision-making process are needed to ensure that older males who undergo screening are those who may potentially benefit,” they noted.
For the study, the authors identified 57,397 men aged 60 and older without a history of prostate cancer who reported undergoing a screening PSA test in the prior 2 years.
Using a risk factor system, mortality risk was estimated based on the scales ranging from 5.5 or less to 10.0 or greater, corresponding to the estimated 10-year mortality of less than 30% to 71% or more, respectively.
Of the men, 19.2% were aged 70 to 74 years, 13.0% were aged 75 to 79 years, and 12.3% were aged 80 years or older. The rest were 69 years or younger.
While the estimated 2-year prostate cancer screening rates were 36.3% among those aged 60 to 64 years and 42.8% for those 65 to 69 years, the rates were even higher, at 47.1%, among those aged 70 to 74 years, and similar, at 42.7%, in the 75 to 79 years of age range. Among those aged 80 years and older, 30.4% had been screened.
While the screening frequency was 43.4% among males with the greatest estimated life expectancy, a fair percentage of men, 30.4%, with the lowest life expectancy, indicative of a 71% or greater risk of death within 10 years, received prostate cancer screening.
In fact, among those with lowest life expectancy, the screening rates were greater than 20% in all age groups.
Screening in Older Age: Benefit in Reducing Mortality Low
Autopsy research indicates that, in fact, as many as 50% of men do have prostate cancer at age 80; however, many of those tumors are low-risk and unlikely to affect the health of the men.
If detected early, as is the intention of screening, prostate cancer can take years to advance and the likelihood of receiving any mortality benefit from continued screening in older age is low.
Furthermore, screening in older age can have implications, including a higher risk of complications following a false positive prostate biopsy that may not have been necessary in the first place, the authors explained.
“Given the long natural history of prostate cancer and lead time associated with PSA-based screening, these males [aged 70 and older or with a high risk of death within 10 years] have a low likelihood of receiving any mortality benefit from continued screening,” the authors reported.
“Yet they face the potential harms of overdiagnosis, such as complications after prostate biopsy for a false-positive screening and psychological stress associated with a cancer diagnosis.”
Guideline Confusion, Habit, Among Reasons for Continued Screening
Among key reasons for the continued screening of men well into old age is the fluctuating history of the guidelines, Dr. Kensler said in an interview.
“There has been considerable variation in prostate cancer screening guidelines over time and across organizations that make screening recommendations, and this has inevitably led to some confusion among clinicians,” he explained.
However, the evidence of a lack of benefit over the age of 70 is strong enough that not performing PSA-based screening among men ages 70 or older is a Healthcare Effectiveness Data and Information Set (HEDIS) measure for quality of care, he noted.
Nevertheless, “I think the trends we found in our analysis reflect that it is difficult for patients and providers to stop providing screening once they have already started it,” Dr. Kensler said.
Another motivator may be an inclination by clinicians to err on the side of caution, he added.
“For clinicians, although they may be aware of the guidelines, they may perhaps fear that they will not have offered screening to one of the older individuals who would have benefited from it even though they recognize that most would not,” Dr. Kensler noted.
Too often, however, such screenings “can lead to a cascade of other events that end up harming the patient without extending their lifespan,” he said.
Difficult Discussions
Complicating matters is the task of informing patients that due to their life expectancy, screening is considered to not likely be worthwhile — which may not be an easy discussion.
“For patients, hearing that they are at a stage of life where they may not benefit from screening is an unpleasant message to receive,” Dr. Kensler said.
“Having an in-depth conversation on this topic is also difficult given the many other health topics that clinicians and patients must cover during a visit.”
Ultimately, “these and other factors lead to inertia, where it is easier to stick to the status quo of continuing screening.”
The challenges underscore the need for improvements to the shared decision-making process to make sure that older men who do undergo prostrate screening will benefit, Dr. Kensler argued.
“If the guidelines are going to recommend shared decision-making, we need to provide tools to help patients and clinicians navigate these potentially difficult conversations.
Life Expectancy Uncertainties
Commenting on the research in an interview, Kyle Richards, MD, associate professor with the Department of Urology at the University of Wisconsin School of Medicine and Public Health, in Madison, noted that, “while most urology experts agree that we should not screen for prostate cancer in men with less than 5-10 years life expectancy, the challenge is deciding which patients have a more limited life expectancy.”
Tools and calculators are available to try to calculate life expectancy, “but they can be cumbersome and difficult to incorporate into clinical practice,” he added.
Indeed, the difficulty in accurately estimating life expectancy is also a limitation of the study, he noted.
“The challenge with a study like this is it is very difficult to accurately estimate life expectancy,” he said. “It is easy to pick a cut point (i.e. age 70) but it is very difficult to calculate one’s life expectancy from survey data alone.”
Another limitation is that “screening PSA testing implies that the patient is not having any symptoms, and we do not know from this study if any of these men were getting PSA checks due to some urinary symptoms or other issues,” Dr. Richards added.
“So, while the study does raise some concern about screening PSA in older men, the data source makes it quite difficult to home in on this question.”
When it can be estimated, life expectancy can indeed provide a more useful guide in assessing the options if a patient is found to have prostate cancer, Dr. Richards noted.
“If a patient has a 5- to 10-year life expectancy, and they are diagnosed with a clinically significant prostate cancer, they absolutely may still benefit from treatment,” he said.
“If they have a clinically significant prostate cancer that is unrecognized, it could metastasize and cause symptoms or lead to death, as roughly 30,000 men die from prostate cancer each year in the USA.”
However, “if a patient has a limited life expectancy of less than 5 to 10 years, don’t screen for prostate cancer,” he advised. Proper guidance should furthermore be made loud and clear in guideline recommendations.
“I do think the USPSTF and AUA need to be the primary voices educating primary care and patients regarding prostate cancer screening,” Dr. Richards said.
“We need to be smart about whom to screen, when to screen, and how often to screen. And this message needs to be heard by the primary care providers that perform the screening.”
The study was supported by the Sandra and Edward Meyer Cancer Center and a grant from the National Cancer Institute of the National Institutes of Health.
Dr. Kensler and Dr. Richards had no disclosures to report.
In its most recent guidance, the US Preventive Services Task Force (USPSTF) revised a previous 2012 recommendation against routine screening for prostate cancer to instead endorse individual decision-making for men aged 55 to 69 years (grade C).
In the update guidance, which was published in 2018, the task force still recommended against PSA-based screening for prostate cancer in men 70 years and older (grade D) due to a range of potential risks and harms. Guidelines from the American Urological Association and American Cancer Society have echoed that recommendation, in general agreement that men over the age of 70 or with limited life expectancy show little benefit from the screening.
To take a closer look at how commonly men are being screened for prostate cancer, based not only on their age but their estimated life expectancy, Kevin H. Kensler, ScD, of Weill Cornell Medicine, and colleagues conducted a cross-sectional study using data from the 2020 Behavioral Risk Factor Surveillance System (BRFSS).
“Our findings indicate that many males aged 70 years and older or those with a high risk of death within 10 years undergo prostate cancer screening despite the recommendation against screening in these populations by current guidelines,” the authors wrote in their paper, published in JAMA Network Open. The results underscore that “enhancements to the shared decision-making process are needed to ensure that older males who undergo screening are those who may potentially benefit,” they noted.
For the study, the authors identified 57,397 men aged 60 and older without a history of prostate cancer who reported undergoing a screening PSA test in the prior 2 years.
Using a risk factor system, mortality risk was estimated based on the scales ranging from 5.5 or less to 10.0 or greater, corresponding to the estimated 10-year mortality of less than 30% to 71% or more, respectively.
Of the men, 19.2% were aged 70 to 74 years, 13.0% were aged 75 to 79 years, and 12.3% were aged 80 years or older. The rest were 69 years or younger.
While the estimated 2-year prostate cancer screening rates were 36.3% among those aged 60 to 64 years and 42.8% for those 65 to 69 years, the rates were even higher, at 47.1%, among those aged 70 to 74 years, and similar, at 42.7%, in the 75 to 79 years of age range. Among those aged 80 years and older, 30.4% had been screened.
While the screening frequency was 43.4% among males with the greatest estimated life expectancy, a fair percentage of men, 30.4%, with the lowest life expectancy, indicative of a 71% or greater risk of death within 10 years, received prostate cancer screening.
In fact, among those with lowest life expectancy, the screening rates were greater than 20% in all age groups.
Screening in Older Age: Benefit in Reducing Mortality Low
Autopsy research indicates that, in fact, as many as 50% of men do have prostate cancer at age 80; however, many of those tumors are low-risk and unlikely to affect the health of the men.
If detected early, as is the intention of screening, prostate cancer can take years to advance and the likelihood of receiving any mortality benefit from continued screening in older age is low.
Furthermore, screening in older age can have implications, including a higher risk of complications following a false positive prostate biopsy that may not have been necessary in the first place, the authors explained.
“Given the long natural history of prostate cancer and lead time associated with PSA-based screening, these males [aged 70 and older or with a high risk of death within 10 years] have a low likelihood of receiving any mortality benefit from continued screening,” the authors reported.
“Yet they face the potential harms of overdiagnosis, such as complications after prostate biopsy for a false-positive screening and psychological stress associated with a cancer diagnosis.”
Guideline Confusion, Habit, Among Reasons for Continued Screening
Among key reasons for the continued screening of men well into old age is the fluctuating history of the guidelines, Dr. Kensler said in an interview.
“There has been considerable variation in prostate cancer screening guidelines over time and across organizations that make screening recommendations, and this has inevitably led to some confusion among clinicians,” he explained.
However, the evidence of a lack of benefit over the age of 70 is strong enough that not performing PSA-based screening among men ages 70 or older is a Healthcare Effectiveness Data and Information Set (HEDIS) measure for quality of care, he noted.
Nevertheless, “I think the trends we found in our analysis reflect that it is difficult for patients and providers to stop providing screening once they have already started it,” Dr. Kensler said.
Another motivator may be an inclination by clinicians to err on the side of caution, he added.
“For clinicians, although they may be aware of the guidelines, they may perhaps fear that they will not have offered screening to one of the older individuals who would have benefited from it even though they recognize that most would not,” Dr. Kensler noted.
Too often, however, such screenings “can lead to a cascade of other events that end up harming the patient without extending their lifespan,” he said.
Difficult Discussions
Complicating matters is the task of informing patients that due to their life expectancy, screening is considered to not likely be worthwhile — which may not be an easy discussion.
“For patients, hearing that they are at a stage of life where they may not benefit from screening is an unpleasant message to receive,” Dr. Kensler said.
“Having an in-depth conversation on this topic is also difficult given the many other health topics that clinicians and patients must cover during a visit.”
Ultimately, “these and other factors lead to inertia, where it is easier to stick to the status quo of continuing screening.”
The challenges underscore the need for improvements to the shared decision-making process to make sure that older men who do undergo prostrate screening will benefit, Dr. Kensler argued.
“If the guidelines are going to recommend shared decision-making, we need to provide tools to help patients and clinicians navigate these potentially difficult conversations.
Life Expectancy Uncertainties
Commenting on the research in an interview, Kyle Richards, MD, associate professor with the Department of Urology at the University of Wisconsin School of Medicine and Public Health, in Madison, noted that, “while most urology experts agree that we should not screen for prostate cancer in men with less than 5-10 years life expectancy, the challenge is deciding which patients have a more limited life expectancy.”
Tools and calculators are available to try to calculate life expectancy, “but they can be cumbersome and difficult to incorporate into clinical practice,” he added.
Indeed, the difficulty in accurately estimating life expectancy is also a limitation of the study, he noted.
“The challenge with a study like this is it is very difficult to accurately estimate life expectancy,” he said. “It is easy to pick a cut point (i.e. age 70) but it is very difficult to calculate one’s life expectancy from survey data alone.”
Another limitation is that “screening PSA testing implies that the patient is not having any symptoms, and we do not know from this study if any of these men were getting PSA checks due to some urinary symptoms or other issues,” Dr. Richards added.
“So, while the study does raise some concern about screening PSA in older men, the data source makes it quite difficult to home in on this question.”
When it can be estimated, life expectancy can indeed provide a more useful guide in assessing the options if a patient is found to have prostate cancer, Dr. Richards noted.
“If a patient has a 5- to 10-year life expectancy, and they are diagnosed with a clinically significant prostate cancer, they absolutely may still benefit from treatment,” he said.
“If they have a clinically significant prostate cancer that is unrecognized, it could metastasize and cause symptoms or lead to death, as roughly 30,000 men die from prostate cancer each year in the USA.”
However, “if a patient has a limited life expectancy of less than 5 to 10 years, don’t screen for prostate cancer,” he advised. Proper guidance should furthermore be made loud and clear in guideline recommendations.
“I do think the USPSTF and AUA need to be the primary voices educating primary care and patients regarding prostate cancer screening,” Dr. Richards said.
“We need to be smart about whom to screen, when to screen, and how often to screen. And this message needs to be heard by the primary care providers that perform the screening.”
The study was supported by the Sandra and Edward Meyer Cancer Center and a grant from the National Cancer Institute of the National Institutes of Health.
Dr. Kensler and Dr. Richards had no disclosures to report.
Survey Spotlights Identification of Dermatologic Adverse Events From Cancer Therapies
“New cancer therapies have brought a diversity of treatment-related dermatologic adverse events (dAEs) beyond those experienced with conventional chemotherapy, which has demanded an evolving assessment of toxicities,” researchers led by Nicole R. LeBoeuf, MD, MPH, of the Department of Dermatology at Brigham and Women’s Hospital and the Center for Cutaneous Oncology at the Dana-Farber Brigham Cancer Center, Boston, wrote in a poster presented at the American Academy of Dermatology annual meeting.
The authors noted that “Version 5.0 of the Common Terminology Criteria for Adverse Events (CTCAE v5.0)” serves as the current, broadly accepted criteria for classification and grading during routine medical care and clinical trials. But despite extensive utilization of CTCAE, there is little data regarding its application.”
To evaluate how CTCAE is being used in clinical practice, they sent a four-case survey of dAEs to 81 dermatologists and 182 medical oncologists at six US-based academic institutions. For three of the cases, respondents were asked to classify and grade morbilliform, psoriasiform, and papulopustular rashes based on a review of photographs and text descriptions. For the fourth case, respondents were asked to grade a dAE using only a clinic note text description. The researchers used chi-square tests in R software to compare survey responses.
Compared with medical oncologists, dermatologists were significantly more likely to provide correct responses in characterizing morbilliform and psoriasiform eruptions. “As low as 12%” of medical oncologists were correct, and “as low as 87%” of dermatologists were correct (P < .001). Similarly, dermatologists were significantly more likely to grade the psoriasiform, papulopustular, and written cases correctly compared with medical oncologists (P < .001 for all associations).
“These cases demonstrated poor concordance of classification and grading between specialties and across medical oncology,” the authors concluded in their poster, noting that 87% of medical oncologists were interested in additional educational tools on dAEs. “With correct classification as low as 12%, medical oncologists may have more difficulty delivering appropriate, toxicity-specific therapy and may consider banal eruptions dangerous.”
Poor concordance of grading among the two groups of clinicians “raises the question of whether CTCAE v5.0 is an appropriate determinant for patient continuation on therapy or in trials,” they added. “As anticancer therapy becomes more complex — with new toxicities from novel agents and combinations — we must ensure we have a grading system that is valid across investigators and does not harm patients by instituting unnecessary treatment stops.”
Future studies, they said, “can explore what interventions beyond involvement of dermatologists improve classification and grading in practice.”
Adam Friedman, MD, professor and chair of dermatology at George Washington University, Washington, who was asked to comment on the study, noted that with the continued expansion and introduction of new targeted and immunotherapies in the oncology space, “you can be sure we will continue to appreciate the importance and value of the field of supportive oncodermatology, as hair, skin, and nails are almost guaranteed collateral damage in this story.
“Ensuring early identification and consistent grading severity is not only important for the plethora of patients who are currently developing the litany of cutaneous adverse events but to evaluate potential mitigation strategies and even push along countermeasures down the FDA approval pathway,” Dr. Friedman said. In this study, the investigators demonstrated that work “is sorely needed, not just in dermatology but even more so for our colleagues across the aisle. A central tenet of supportive oncodermatology must also be education for all stakeholders, and the good news is our oncology partners will welcome it.”
Dr. LeBoeuf disclosed that she is a consultant to and has received honoraria from Bayer, Seattle Genetics, Sanofi, Silverback, Fortress Biotech, and Synox Therapeutics outside the submitted work. No other authors reported having financial disclosures. Dr. Friedman directs the supportive oncodermatology program at GW that received independent funding from La Roche-Posay.
A version of this article first appeared on Medscape.com.
“New cancer therapies have brought a diversity of treatment-related dermatologic adverse events (dAEs) beyond those experienced with conventional chemotherapy, which has demanded an evolving assessment of toxicities,” researchers led by Nicole R. LeBoeuf, MD, MPH, of the Department of Dermatology at Brigham and Women’s Hospital and the Center for Cutaneous Oncology at the Dana-Farber Brigham Cancer Center, Boston, wrote in a poster presented at the American Academy of Dermatology annual meeting.
The authors noted that “Version 5.0 of the Common Terminology Criteria for Adverse Events (CTCAE v5.0)” serves as the current, broadly accepted criteria for classification and grading during routine medical care and clinical trials. But despite extensive utilization of CTCAE, there is little data regarding its application.”
To evaluate how CTCAE is being used in clinical practice, they sent a four-case survey of dAEs to 81 dermatologists and 182 medical oncologists at six US-based academic institutions. For three of the cases, respondents were asked to classify and grade morbilliform, psoriasiform, and papulopustular rashes based on a review of photographs and text descriptions. For the fourth case, respondents were asked to grade a dAE using only a clinic note text description. The researchers used chi-square tests in R software to compare survey responses.
Compared with medical oncologists, dermatologists were significantly more likely to provide correct responses in characterizing morbilliform and psoriasiform eruptions. “As low as 12%” of medical oncologists were correct, and “as low as 87%” of dermatologists were correct (P < .001). Similarly, dermatologists were significantly more likely to grade the psoriasiform, papulopustular, and written cases correctly compared with medical oncologists (P < .001 for all associations).
“These cases demonstrated poor concordance of classification and grading between specialties and across medical oncology,” the authors concluded in their poster, noting that 87% of medical oncologists were interested in additional educational tools on dAEs. “With correct classification as low as 12%, medical oncologists may have more difficulty delivering appropriate, toxicity-specific therapy and may consider banal eruptions dangerous.”
Poor concordance of grading among the two groups of clinicians “raises the question of whether CTCAE v5.0 is an appropriate determinant for patient continuation on therapy or in trials,” they added. “As anticancer therapy becomes more complex — with new toxicities from novel agents and combinations — we must ensure we have a grading system that is valid across investigators and does not harm patients by instituting unnecessary treatment stops.”
Future studies, they said, “can explore what interventions beyond involvement of dermatologists improve classification and grading in practice.”
Adam Friedman, MD, professor and chair of dermatology at George Washington University, Washington, who was asked to comment on the study, noted that with the continued expansion and introduction of new targeted and immunotherapies in the oncology space, “you can be sure we will continue to appreciate the importance and value of the field of supportive oncodermatology, as hair, skin, and nails are almost guaranteed collateral damage in this story.
“Ensuring early identification and consistent grading severity is not only important for the plethora of patients who are currently developing the litany of cutaneous adverse events but to evaluate potential mitigation strategies and even push along countermeasures down the FDA approval pathway,” Dr. Friedman said. In this study, the investigators demonstrated that work “is sorely needed, not just in dermatology but even more so for our colleagues across the aisle. A central tenet of supportive oncodermatology must also be education for all stakeholders, and the good news is our oncology partners will welcome it.”
Dr. LeBoeuf disclosed that she is a consultant to and has received honoraria from Bayer, Seattle Genetics, Sanofi, Silverback, Fortress Biotech, and Synox Therapeutics outside the submitted work. No other authors reported having financial disclosures. Dr. Friedman directs the supportive oncodermatology program at GW that received independent funding from La Roche-Posay.
A version of this article first appeared on Medscape.com.
“New cancer therapies have brought a diversity of treatment-related dermatologic adverse events (dAEs) beyond those experienced with conventional chemotherapy, which has demanded an evolving assessment of toxicities,” researchers led by Nicole R. LeBoeuf, MD, MPH, of the Department of Dermatology at Brigham and Women’s Hospital and the Center for Cutaneous Oncology at the Dana-Farber Brigham Cancer Center, Boston, wrote in a poster presented at the American Academy of Dermatology annual meeting.
The authors noted that “Version 5.0 of the Common Terminology Criteria for Adverse Events (CTCAE v5.0)” serves as the current, broadly accepted criteria for classification and grading during routine medical care and clinical trials. But despite extensive utilization of CTCAE, there is little data regarding its application.”
To evaluate how CTCAE is being used in clinical practice, they sent a four-case survey of dAEs to 81 dermatologists and 182 medical oncologists at six US-based academic institutions. For three of the cases, respondents were asked to classify and grade morbilliform, psoriasiform, and papulopustular rashes based on a review of photographs and text descriptions. For the fourth case, respondents were asked to grade a dAE using only a clinic note text description. The researchers used chi-square tests in R software to compare survey responses.
Compared with medical oncologists, dermatologists were significantly more likely to provide correct responses in characterizing morbilliform and psoriasiform eruptions. “As low as 12%” of medical oncologists were correct, and “as low as 87%” of dermatologists were correct (P < .001). Similarly, dermatologists were significantly more likely to grade the psoriasiform, papulopustular, and written cases correctly compared with medical oncologists (P < .001 for all associations).
“These cases demonstrated poor concordance of classification and grading between specialties and across medical oncology,” the authors concluded in their poster, noting that 87% of medical oncologists were interested in additional educational tools on dAEs. “With correct classification as low as 12%, medical oncologists may have more difficulty delivering appropriate, toxicity-specific therapy and may consider banal eruptions dangerous.”
Poor concordance of grading among the two groups of clinicians “raises the question of whether CTCAE v5.0 is an appropriate determinant for patient continuation on therapy or in trials,” they added. “As anticancer therapy becomes more complex — with new toxicities from novel agents and combinations — we must ensure we have a grading system that is valid across investigators and does not harm patients by instituting unnecessary treatment stops.”
Future studies, they said, “can explore what interventions beyond involvement of dermatologists improve classification and grading in practice.”
Adam Friedman, MD, professor and chair of dermatology at George Washington University, Washington, who was asked to comment on the study, noted that with the continued expansion and introduction of new targeted and immunotherapies in the oncology space, “you can be sure we will continue to appreciate the importance and value of the field of supportive oncodermatology, as hair, skin, and nails are almost guaranteed collateral damage in this story.
“Ensuring early identification and consistent grading severity is not only important for the plethora of patients who are currently developing the litany of cutaneous adverse events but to evaluate potential mitigation strategies and even push along countermeasures down the FDA approval pathway,” Dr. Friedman said. In this study, the investigators demonstrated that work “is sorely needed, not just in dermatology but even more so for our colleagues across the aisle. A central tenet of supportive oncodermatology must also be education for all stakeholders, and the good news is our oncology partners will welcome it.”
Dr. LeBoeuf disclosed that she is a consultant to and has received honoraria from Bayer, Seattle Genetics, Sanofi, Silverback, Fortress Biotech, and Synox Therapeutics outside the submitted work. No other authors reported having financial disclosures. Dr. Friedman directs the supportive oncodermatology program at GW that received independent funding from La Roche-Posay.
A version of this article first appeared on Medscape.com.
FROM AAD 2024
New mRNA Vaccines in Development for Cancer and Infections
Martina Prelog, MD, a pediatric and adolescent medicine specialist at the University Hospital of Würzburg in Germany, reported on the principles, research status, and perspectives for these vaccines at the 25th Travel and Health Forum of the Center for Travel Medicine in Berlin.
To understand the future, the immunologist first examined the past. “The induction of cellular and humoral immune responses by externally injected mRNA was discovered in the 1990s,” she said.
Instability Challenge
Significant hurdles in mRNA vaccinations included the instability of mRNA and the immune system’s ability to identify foreign mRNA as a threat and destroy mRNA fragments. “The breakthrough toward vaccination came through Dr. Katalin Karikó, who, along with Dr. Drew Weissman, both of the University of Pennsylvania School of Medicine, discovered in 2005 that modifications of mRNA (replacing the nucleoside uridine with pseudouridine) enable better stability of mRNA, reduced immunogenicity, and higher translational capacity at the ribosomes,” said Dr. Prelog.
With this discovery, the two researchers paved the way for the development of mRNA vaccines against COVID-19 and other diseases. They were awarded the Nobel Prize in medicine for their discovery last year.
Improved Scalability
“Since 2009, mRNA vaccines have been studied as a treatment option for cancer,” said Dr. Prelog. “Since 2012, they have been studied for the influenza virus and respiratory syncytial virus [RSV].” Consequently, several mRNA vaccines are currently in development or in approval studies. “The mRNA technology offers the advantage of quickly and flexibly responding to new variants of pathogens and the ability to scale up production when there is high demand for a particular vaccine.”
Different forms and designations of mRNA vaccines are used, depending on the application and desired effect, said Dr. Prelog.
In nucleoside-modified mRNA vaccines, modifications in the mRNA sequence enable the mRNA to remain in the body longer and to induce protein synthesis more effectively.
Lipid nanoparticle (LNP)–encapsulated mRNA vaccines protect the coding mRNA sequences against degradation by the body’s enzymes and facilitate the uptake of mRNA into cells, where it then triggers the production of the desired protein. In addition, LNPs are involved in cell stimulation and support the self-adjuvant effect of mRNA vaccines, thus eliminating the need for adjuvants.
Self-amplifying mRNA vaccines include a special mRNA that replicates itself in the cell and contains a sequence for RNA replicase, in addition to the coding sequence for the protein. This composition enables increased production of the target protein without the need for a high amount of external mRNA administration. Such vaccines could trigger a longer and stronger immune response because the immune system has more time to interact with the protein.
Cancer Immunotherapy
Dr. Prelog also discussed personalized vaccines for cancer immunotherapy. Personalized mRNA vaccines are tailored to the patient’s genetic characteristics and antigens. They could be used in cancer immunotherapy to activate the immune system selectively against tumor cells.
Multivalent mRNA vaccines contain mRNA that codes for multiple antigens rather than just one protein to generate an immune response. These vaccines could be particularly useful in fighting pathogens with variable or changing surface structures or in eliciting protection against multiple pathogens simultaneously.
The technology of mRNA-encoded antibodies involves introducing mRNA into the cell, which creates light and heavy chains of antibodies. This step leads to the formation of antibodies targeted against toxins (eg, diphtheria and tetanus), animal venoms, infectious agents, or tumor cells.
Genetic Engineering
Dr. Prelog also reviewed genetic engineering techniques. In regenerative therapy or protein replacement therapy, skin fibroblasts or other cells are transfected with mRNA to enable conversion into induced pluripotent stem cells. This approach avoids the risk for DNA integration into the genome and associated mutation risks.
Another approach is making post-transcriptional modifications through RNA interference. For example, RNA structures can be used to inhibit the translation of disease-causing proteins. This technique is currently being tested against HIV and tumors such as melanoma.
In addition, mRNA technologies can be combined with CRISPR/Cas9 technology (“gene scissors”) to influence the creation of gene products even more precisely. The advantage of this technique is that mRNA is only transiently expressed, thus preventing unwanted side effects. Furthermore, mRNA is translated directly in the cytoplasm, leading to a faster initiation of gene editing.
Of the numerous ongoing clinical mRNA vaccine studies, around 70% focus on infections, about 12% on cancer, and the rest on autoimmune diseases and neurodegenerative disorders, said Dr. Prelog.
Research in Infections
Research in the fields of infectious diseases and oncology is the most advanced: mRNA vaccines against influenza and RSV are already in advanced clinical trials, Dr. Prelog told this news organization.
“Conventional influenza vaccines contain immunogenic surface molecules against hemagglutinin and neuraminidase in various combinations of influenza strains A and B and are produced in egg or cell cultures,” she said. “This is a time-consuming manufacturing process that takes months and, particularly with the egg-based process, bears the risk of changing the vaccine strain.”
“Additionally, influenza viruses undergo antigenic shift and drift through recombination, thus requiring annual adjustments to the vaccines. Thus, these influenza vaccines often lose accuracy in targeting circulating seasonal influenza strains.”
Several mRNA vaccines being tested contain not only coding sequences against hemagglutinin and neuraminidase but also for structural proteins of influenza viruses. “These are more conserved and mutate less easily, meaning they could serve as the basis for universal pandemic influenza vaccines,” said Dr. Prelog.
An advantage of mRNA vaccines, she added, is the strong cellular immune response that they elicit. This response is intended to provide additional protection alongside specific antibodies. An mRNA vaccine with coding sequences for the pre-fusion protein of RSV is in phase 3 trials for approval for vaccination in patients aged 60 years and older. It shows high effectiveness even in older patients and those with comorbidities.
Elaborate Purification Process
Bacterial origin plasmid DNA is used to produce mRNA vaccines. The mRNA vaccines for COVID-19 raised concerns that production-related DNA residues could pose a safety risk and cause autoimmune diseases.
These vaccines “typically undergo a very elaborate purification process,” said Dr. Prelog. “This involves enzymatic digestion with DNase to fragment and deplete plasmid DNA, followed by purification using chromatography columns, so that no safety-relevant DNA fragments should remain afterward.”
Thus, the Paul-Ehrlich-Institut also pointed out the very small, fragmented plasmid DNA residues of bacterial origin in mRNA COVID-19 vaccines pose no risk, unlike residual DNA from animal cell culture might pose in other vaccines.
Prevention and Therapy
In addition to the numerous advantages of mRNA vaccines (such as rapid adaptability to new or mutated pathogens, scalability, rapid production capability, self-adjuvant effect, strong induction of cellular immune responses, and safety), there are also challenges in RNA technology as a preventive and therapeutic measure, according to Dr. Prelog.
“Stability and storability, as well as the costs of new vaccine developments, play a role, as do the long-term effects regarding the persistence of antibody and cellular responses,” she said. The COVID-19 mRNA vaccines, for example, showed a well-maintained cellular immune response despite a tendency toward a rapid decline in humoral immune response.
“The experience with COVID-19 mRNA vaccines and the new vaccine developments based on mRNA technology give hope for an efficient and safe preventive and therapeutic use, particularly in the fields of infectious diseases and oncology,” Dr. Prelog concluded.
This story was translated from the Medscape German edition using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.
Martina Prelog, MD, a pediatric and adolescent medicine specialist at the University Hospital of Würzburg in Germany, reported on the principles, research status, and perspectives for these vaccines at the 25th Travel and Health Forum of the Center for Travel Medicine in Berlin.
To understand the future, the immunologist first examined the past. “The induction of cellular and humoral immune responses by externally injected mRNA was discovered in the 1990s,” she said.
Instability Challenge
Significant hurdles in mRNA vaccinations included the instability of mRNA and the immune system’s ability to identify foreign mRNA as a threat and destroy mRNA fragments. “The breakthrough toward vaccination came through Dr. Katalin Karikó, who, along with Dr. Drew Weissman, both of the University of Pennsylvania School of Medicine, discovered in 2005 that modifications of mRNA (replacing the nucleoside uridine with pseudouridine) enable better stability of mRNA, reduced immunogenicity, and higher translational capacity at the ribosomes,” said Dr. Prelog.
With this discovery, the two researchers paved the way for the development of mRNA vaccines against COVID-19 and other diseases. They were awarded the Nobel Prize in medicine for their discovery last year.
Improved Scalability
“Since 2009, mRNA vaccines have been studied as a treatment option for cancer,” said Dr. Prelog. “Since 2012, they have been studied for the influenza virus and respiratory syncytial virus [RSV].” Consequently, several mRNA vaccines are currently in development or in approval studies. “The mRNA technology offers the advantage of quickly and flexibly responding to new variants of pathogens and the ability to scale up production when there is high demand for a particular vaccine.”
Different forms and designations of mRNA vaccines are used, depending on the application and desired effect, said Dr. Prelog.
In nucleoside-modified mRNA vaccines, modifications in the mRNA sequence enable the mRNA to remain in the body longer and to induce protein synthesis more effectively.
Lipid nanoparticle (LNP)–encapsulated mRNA vaccines protect the coding mRNA sequences against degradation by the body’s enzymes and facilitate the uptake of mRNA into cells, where it then triggers the production of the desired protein. In addition, LNPs are involved in cell stimulation and support the self-adjuvant effect of mRNA vaccines, thus eliminating the need for adjuvants.
Self-amplifying mRNA vaccines include a special mRNA that replicates itself in the cell and contains a sequence for RNA replicase, in addition to the coding sequence for the protein. This composition enables increased production of the target protein without the need for a high amount of external mRNA administration. Such vaccines could trigger a longer and stronger immune response because the immune system has more time to interact with the protein.
Cancer Immunotherapy
Dr. Prelog also discussed personalized vaccines for cancer immunotherapy. Personalized mRNA vaccines are tailored to the patient’s genetic characteristics and antigens. They could be used in cancer immunotherapy to activate the immune system selectively against tumor cells.
Multivalent mRNA vaccines contain mRNA that codes for multiple antigens rather than just one protein to generate an immune response. These vaccines could be particularly useful in fighting pathogens with variable or changing surface structures or in eliciting protection against multiple pathogens simultaneously.
The technology of mRNA-encoded antibodies involves introducing mRNA into the cell, which creates light and heavy chains of antibodies. This step leads to the formation of antibodies targeted against toxins (eg, diphtheria and tetanus), animal venoms, infectious agents, or tumor cells.
Genetic Engineering
Dr. Prelog also reviewed genetic engineering techniques. In regenerative therapy or protein replacement therapy, skin fibroblasts or other cells are transfected with mRNA to enable conversion into induced pluripotent stem cells. This approach avoids the risk for DNA integration into the genome and associated mutation risks.
Another approach is making post-transcriptional modifications through RNA interference. For example, RNA structures can be used to inhibit the translation of disease-causing proteins. This technique is currently being tested against HIV and tumors such as melanoma.
In addition, mRNA technologies can be combined with CRISPR/Cas9 technology (“gene scissors”) to influence the creation of gene products even more precisely. The advantage of this technique is that mRNA is only transiently expressed, thus preventing unwanted side effects. Furthermore, mRNA is translated directly in the cytoplasm, leading to a faster initiation of gene editing.
Of the numerous ongoing clinical mRNA vaccine studies, around 70% focus on infections, about 12% on cancer, and the rest on autoimmune diseases and neurodegenerative disorders, said Dr. Prelog.
Research in Infections
Research in the fields of infectious diseases and oncology is the most advanced: mRNA vaccines against influenza and RSV are already in advanced clinical trials, Dr. Prelog told this news organization.
“Conventional influenza vaccines contain immunogenic surface molecules against hemagglutinin and neuraminidase in various combinations of influenza strains A and B and are produced in egg or cell cultures,” she said. “This is a time-consuming manufacturing process that takes months and, particularly with the egg-based process, bears the risk of changing the vaccine strain.”
“Additionally, influenza viruses undergo antigenic shift and drift through recombination, thus requiring annual adjustments to the vaccines. Thus, these influenza vaccines often lose accuracy in targeting circulating seasonal influenza strains.”
Several mRNA vaccines being tested contain not only coding sequences against hemagglutinin and neuraminidase but also for structural proteins of influenza viruses. “These are more conserved and mutate less easily, meaning they could serve as the basis for universal pandemic influenza vaccines,” said Dr. Prelog.
An advantage of mRNA vaccines, she added, is the strong cellular immune response that they elicit. This response is intended to provide additional protection alongside specific antibodies. An mRNA vaccine with coding sequences for the pre-fusion protein of RSV is in phase 3 trials for approval for vaccination in patients aged 60 years and older. It shows high effectiveness even in older patients and those with comorbidities.
Elaborate Purification Process
Bacterial origin plasmid DNA is used to produce mRNA vaccines. The mRNA vaccines for COVID-19 raised concerns that production-related DNA residues could pose a safety risk and cause autoimmune diseases.
These vaccines “typically undergo a very elaborate purification process,” said Dr. Prelog. “This involves enzymatic digestion with DNase to fragment and deplete plasmid DNA, followed by purification using chromatography columns, so that no safety-relevant DNA fragments should remain afterward.”
Thus, the Paul-Ehrlich-Institut also pointed out the very small, fragmented plasmid DNA residues of bacterial origin in mRNA COVID-19 vaccines pose no risk, unlike residual DNA from animal cell culture might pose in other vaccines.
Prevention and Therapy
In addition to the numerous advantages of mRNA vaccines (such as rapid adaptability to new or mutated pathogens, scalability, rapid production capability, self-adjuvant effect, strong induction of cellular immune responses, and safety), there are also challenges in RNA technology as a preventive and therapeutic measure, according to Dr. Prelog.
“Stability and storability, as well as the costs of new vaccine developments, play a role, as do the long-term effects regarding the persistence of antibody and cellular responses,” she said. The COVID-19 mRNA vaccines, for example, showed a well-maintained cellular immune response despite a tendency toward a rapid decline in humoral immune response.
“The experience with COVID-19 mRNA vaccines and the new vaccine developments based on mRNA technology give hope for an efficient and safe preventive and therapeutic use, particularly in the fields of infectious diseases and oncology,” Dr. Prelog concluded.
This story was translated from the Medscape German edition using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.
Martina Prelog, MD, a pediatric and adolescent medicine specialist at the University Hospital of Würzburg in Germany, reported on the principles, research status, and perspectives for these vaccines at the 25th Travel and Health Forum of the Center for Travel Medicine in Berlin.
To understand the future, the immunologist first examined the past. “The induction of cellular and humoral immune responses by externally injected mRNA was discovered in the 1990s,” she said.
Instability Challenge
Significant hurdles in mRNA vaccinations included the instability of mRNA and the immune system’s ability to identify foreign mRNA as a threat and destroy mRNA fragments. “The breakthrough toward vaccination came through Dr. Katalin Karikó, who, along with Dr. Drew Weissman, both of the University of Pennsylvania School of Medicine, discovered in 2005 that modifications of mRNA (replacing the nucleoside uridine with pseudouridine) enable better stability of mRNA, reduced immunogenicity, and higher translational capacity at the ribosomes,” said Dr. Prelog.
With this discovery, the two researchers paved the way for the development of mRNA vaccines against COVID-19 and other diseases. They were awarded the Nobel Prize in medicine for their discovery last year.
Improved Scalability
“Since 2009, mRNA vaccines have been studied as a treatment option for cancer,” said Dr. Prelog. “Since 2012, they have been studied for the influenza virus and respiratory syncytial virus [RSV].” Consequently, several mRNA vaccines are currently in development or in approval studies. “The mRNA technology offers the advantage of quickly and flexibly responding to new variants of pathogens and the ability to scale up production when there is high demand for a particular vaccine.”
Different forms and designations of mRNA vaccines are used, depending on the application and desired effect, said Dr. Prelog.
In nucleoside-modified mRNA vaccines, modifications in the mRNA sequence enable the mRNA to remain in the body longer and to induce protein synthesis more effectively.
Lipid nanoparticle (LNP)–encapsulated mRNA vaccines protect the coding mRNA sequences against degradation by the body’s enzymes and facilitate the uptake of mRNA into cells, where it then triggers the production of the desired protein. In addition, LNPs are involved in cell stimulation and support the self-adjuvant effect of mRNA vaccines, thus eliminating the need for adjuvants.
Self-amplifying mRNA vaccines include a special mRNA that replicates itself in the cell and contains a sequence for RNA replicase, in addition to the coding sequence for the protein. This composition enables increased production of the target protein without the need for a high amount of external mRNA administration. Such vaccines could trigger a longer and stronger immune response because the immune system has more time to interact with the protein.
Cancer Immunotherapy
Dr. Prelog also discussed personalized vaccines for cancer immunotherapy. Personalized mRNA vaccines are tailored to the patient’s genetic characteristics and antigens. They could be used in cancer immunotherapy to activate the immune system selectively against tumor cells.
Multivalent mRNA vaccines contain mRNA that codes for multiple antigens rather than just one protein to generate an immune response. These vaccines could be particularly useful in fighting pathogens with variable or changing surface structures or in eliciting protection against multiple pathogens simultaneously.
The technology of mRNA-encoded antibodies involves introducing mRNA into the cell, which creates light and heavy chains of antibodies. This step leads to the formation of antibodies targeted against toxins (eg, diphtheria and tetanus), animal venoms, infectious agents, or tumor cells.
Genetic Engineering
Dr. Prelog also reviewed genetic engineering techniques. In regenerative therapy or protein replacement therapy, skin fibroblasts or other cells are transfected with mRNA to enable conversion into induced pluripotent stem cells. This approach avoids the risk for DNA integration into the genome and associated mutation risks.
Another approach is making post-transcriptional modifications through RNA interference. For example, RNA structures can be used to inhibit the translation of disease-causing proteins. This technique is currently being tested against HIV and tumors such as melanoma.
In addition, mRNA technologies can be combined with CRISPR/Cas9 technology (“gene scissors”) to influence the creation of gene products even more precisely. The advantage of this technique is that mRNA is only transiently expressed, thus preventing unwanted side effects. Furthermore, mRNA is translated directly in the cytoplasm, leading to a faster initiation of gene editing.
Of the numerous ongoing clinical mRNA vaccine studies, around 70% focus on infections, about 12% on cancer, and the rest on autoimmune diseases and neurodegenerative disorders, said Dr. Prelog.
Research in Infections
Research in the fields of infectious diseases and oncology is the most advanced: mRNA vaccines against influenza and RSV are already in advanced clinical trials, Dr. Prelog told this news organization.
“Conventional influenza vaccines contain immunogenic surface molecules against hemagglutinin and neuraminidase in various combinations of influenza strains A and B and are produced in egg or cell cultures,” she said. “This is a time-consuming manufacturing process that takes months and, particularly with the egg-based process, bears the risk of changing the vaccine strain.”
“Additionally, influenza viruses undergo antigenic shift and drift through recombination, thus requiring annual adjustments to the vaccines. Thus, these influenza vaccines often lose accuracy in targeting circulating seasonal influenza strains.”
Several mRNA vaccines being tested contain not only coding sequences against hemagglutinin and neuraminidase but also for structural proteins of influenza viruses. “These are more conserved and mutate less easily, meaning they could serve as the basis for universal pandemic influenza vaccines,” said Dr. Prelog.
An advantage of mRNA vaccines, she added, is the strong cellular immune response that they elicit. This response is intended to provide additional protection alongside specific antibodies. An mRNA vaccine with coding sequences for the pre-fusion protein of RSV is in phase 3 trials for approval for vaccination in patients aged 60 years and older. It shows high effectiveness even in older patients and those with comorbidities.
Elaborate Purification Process
Bacterial origin plasmid DNA is used to produce mRNA vaccines. The mRNA vaccines for COVID-19 raised concerns that production-related DNA residues could pose a safety risk and cause autoimmune diseases.
These vaccines “typically undergo a very elaborate purification process,” said Dr. Prelog. “This involves enzymatic digestion with DNase to fragment and deplete plasmid DNA, followed by purification using chromatography columns, so that no safety-relevant DNA fragments should remain afterward.”
Thus, the Paul-Ehrlich-Institut also pointed out the very small, fragmented plasmid DNA residues of bacterial origin in mRNA COVID-19 vaccines pose no risk, unlike residual DNA from animal cell culture might pose in other vaccines.
Prevention and Therapy
In addition to the numerous advantages of mRNA vaccines (such as rapid adaptability to new or mutated pathogens, scalability, rapid production capability, self-adjuvant effect, strong induction of cellular immune responses, and safety), there are also challenges in RNA technology as a preventive and therapeutic measure, according to Dr. Prelog.
“Stability and storability, as well as the costs of new vaccine developments, play a role, as do the long-term effects regarding the persistence of antibody and cellular responses,” she said. The COVID-19 mRNA vaccines, for example, showed a well-maintained cellular immune response despite a tendency toward a rapid decline in humoral immune response.
“The experience with COVID-19 mRNA vaccines and the new vaccine developments based on mRNA technology give hope for an efficient and safe preventive and therapeutic use, particularly in the fields of infectious diseases and oncology,” Dr. Prelog concluded.
This story was translated from the Medscape German edition using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication. A version of this article appeared on Medscape.com.
Can a Risk Score Predict Kidney Injury After Cisplatin?
Cisplatin is a preferred treatment for a wide range of cancers, including breast, head and neck, lung, ovary, and more. However, its side effects — particularly nephrotoxicity — can be severe. Kidney injury on cisplatin is associated with higher mortality and can jeopardize a patient’s eligibility for other therapies.
Now, in a large study using data from six US cancer centers, researchers have developed a risk algorithm to predict acute kidney injury (AKI) after cisplatin administration.
A risk prediction calculator based on the algorithm is available online for patients and providers to determine an individual patient›s risk for kidney injury from cisplatin using readily available clinical data.
Other risk scores and risk prediction models have been developed to help clinicians assess in advance whether a patient might develop AKI after receiving cisplatin, so that more careful monitoring, dose adjustments, or an alternative treatment, if available, might be considered.
However, previous models were limited by factors such as small sample sizes, lack of external validation, older data, and liberal definitions of AKI, said Shruti Gupta, MD, MPH, director of onco-nephrology at Brigham and Women’s Hospital (BWH) and Dana-Farber Cancer Institute, and David E. Leaf, MD, MMSc, director of clinical and translational research in AKI, Division of Renal Medicine, BWH, Boston.
Dr. Gupta and Dr. Leaf believe their risk score for predicting severe AKI after intravenous (IV) cisplatin, published online in The BMJ, is “more accurate and generalizable than prior models for several reasons,” they told this news organization in a joint email.
“First, we externally validated our findings across cancer centers other than the one where it was developed,” they said. “Second, we focused on moderate to severe kidney injury, the most clinically relevant form of kidney damage, whereas prior models examined more mild forms of kidney injury. Third, we collected data on nearly 25,000 patients receiving their first dose of IV cisplatin, which is larger than all previous studies combined.”
‘Herculean Effort’
“We conceived of this study back in 2018, contacted collaborators at each participating cancer center, and had numerous meetings to try to gather granular data on patients treated with their first dose of intravenous (IV) cisplatin,” Dr. Gupta and Dr. Leaf explained. They also incorporated patient feedback from focus groups and surveys.
“This was truly a Herculean effort that involved physicians, programmers, research coordinators, and patients,” they said.
The multicenter study included 24,717 patients — 11,766 in the derivation cohort and 12,951 in the validation cohort. Overall, the median age was about 60 years, about 58% were men, and about 78% were White.
The primary outcome was cisplatin-induced AKI (CP-AKI), defined as a twofold or greater increase in serum creatinine or kidney replacement therapy within 14 days of a first dose of IV cisplatin.
Their simple risk score consisting of nine covariates — age, hypertension, type 2 diabetes, hemoglobin level, white blood cell count, platelet count, serum albumin level, serum magnesium level, and cisplatin dose — predicted a higher risk for CP-AKI in both cohorts.
Notably, adding serum creatinine to the model did not change the area under the curve, and therefore, serum creatinine, though also an independent risk factor for CP-AKI, was not included in the score.
Patients in the highest risk category had 24-fold higher odds of CP-AKI in the derivation cohort and close to 18-fold higher odds in the validation cohort than those in the lowest risk category.
The primary model had a C statistic of 0.75 (95% CI, 0.73-0.76) and showed better discrimination for CP-AKI than previously published models, for which the C statistics ranged from 0.60 to 0.68. The first author of a paper on an earlier model, Shveta Motwani, MD, MMSc, of BWH and Dana-Farber Cancer Institute in Boston, is also a coauthor of the new study.
Greater severity of CP-AKI was associated with shorter 90-day survival (adjusted hazard ratio, 4.63; 95% CI, 3.56-6.02) for stage III CP-AKI vs no CP-AKI.
‘Definitive Work’
Joel M. Topf, MD, a nephrologist with expertise in chronic kidney disease in Detroit, who wasn’t involved in the development of the risk score, called the study “a definitive work on an important concept in oncology and nephrology.”
“While this is not the first attempt to devise a risk score, it is by far the biggest,” he told this news organization. Furthermore, the authors “used a diverse population, recruiting patients with a variety of cancers (previous attempts had often used a homogenous diagnosis, putting into question how generalizable the results were) from six different cancer centers.”
In addition, he said, “The authors did not restrict patients with chronic kidney disease or other significant comorbidities and used the geographic diversity to produce a cohort that has an age, gender, racial, and ethnic distribution, which is more representative of the US than previous, single-center attempts to risk score patients.”
An earlier model used the Kidney Disease: Improving Global Outcomes (KDIGO) consensus definition of AKI of an increase in serum creatinine of 0.3 mg/dL, he noted. “While a sensitive definition of AKI, it captures mild, hemodynamic increases in creatinine of questionable significance,” he said.
By contrast, the new score uses KDIGO stage II and above to define AKI. “This is a better choice, as we do not want to dissuade patients and doctors from choosing chemotherapy due to a fear of insignificant kidney damage,” he said.
All that said, Dr. Topf noted that neither the current score nor the earlier model included serum creatinine. “This is curious to me and may represent the small number of patients with representative elevated creatinine in the derivation cohort (only 1.3% with an estimated glomerular filtration rate [eGFR] < 45).”
“Since the cohort is made up of people who received cis-platinum, the low prevalence of eGFRs < 45 may be due to physicians steering away from cis-platinum in this group,” he suggested. “It would be unfortunate if this risk score gave an unintentional ‘green light’ to these patients, exposing them to predictable harm.”
‘Certainly Useful’
Anushree Shirali, MD, an associate professor in the Section of Nephrology and consulting physician, Yale Onco-Nephrology, Yale School of Medicine, in New Haven, Connecticut, said that having a prediction score for which patients are more likely to develop AKI after a single dose of cisplatin would be helpful for oncologists, as well as nephrologists.
As a nephrologist, Dr. Shirali mostly sees patients who already have AKI, she told this news organization. But there are circumstances in which the tool could still be helpful.
“Let’s say someone has abnormal kidney function at baseline — ie, creatinine is higher than the normal range — and they were on dialysis 5 years ago for something else, and now, they have cancer and may be given cisplatin. They worry about their chances of getting AKI and needing dialysis again,” she said. “That’s just one scenario in which I might be asked to answer that question and the tool would certainly be useful.”
Other scenarios could include someone who has just one kidney because they donated a kidney for transplant years ago, and now, they have a malignancy and wonder what their actual risk is of getting kidney issues on cisplatin.
Oncologists could use the tool to determine whether a patient should be treated with cisplatin, or if they’re at high risk, whether an alternative that’s not nephrotoxic might be used. By contrast, “if somebody’s low risk and an oncologist thinks cisplatin is the best agent they have, then they might want to go ahead and use it,” Dr. Shirali said.
Future research could take into consideration that CP-AKI is dose dependent, she suggested, because a prediction score that included the number of cisplatin doses could be even more helpful to determine risk. And, even though the derivation and validation cohorts for the new tool are representative of the US population, additional research should also include more racial/ethnic diversity, she said.
Dr. Gupta and Dr. Leaf hope their tool “will be utilized immediately by patients and providers to help predict an individual’s risk of cisplatin-associated kidney damage. It is easy to use, available for free online, and incorporates readily available clinical variables.”
If a patient is at high risk, the clinical team can consider preventive measures such as administering more IV fluids before receiving cisplatin or monitoring kidney function more closely afterward, they suggested.
Dr. Gupta reported research support from the National Institutes of Health (NIH) and the National Institute of Diabetes and Digestive and Kidney Diseases. She also reported research funding from BTG International, GE HealthCare, and AstraZeneca outside the submitted work. She is a member of GlaxoSmithKline’s Global Anemia Council, a consultant for Secretome and Proletariat Therapeutics, and founder and president emeritus of the American Society of Onconephrology (unpaid). Dr. Leaf is supported by NIH grants, reported research support from BioPorto, BTG International, and Metro International Biotech, and has served as a consultant. Dr. Topf reported an ownership stake in a few DaVita-run dialysis clinics. He also runs a vascular access center and has participated in advisory boards with Cara Therapeutics, Vifor, Astra Zeneca, Bayer, Renibus Therapeutics, Travere Therapeutics, and GlaxoSmithKline. He is president of NephJC, a nonprofit educational organization with no industry support. Dr. Shirali declared no competing interests.
A version of this article appeared on Medscape.com.
Cisplatin is a preferred treatment for a wide range of cancers, including breast, head and neck, lung, ovary, and more. However, its side effects — particularly nephrotoxicity — can be severe. Kidney injury on cisplatin is associated with higher mortality and can jeopardize a patient’s eligibility for other therapies.
Now, in a large study using data from six US cancer centers, researchers have developed a risk algorithm to predict acute kidney injury (AKI) after cisplatin administration.
A risk prediction calculator based on the algorithm is available online for patients and providers to determine an individual patient›s risk for kidney injury from cisplatin using readily available clinical data.
Other risk scores and risk prediction models have been developed to help clinicians assess in advance whether a patient might develop AKI after receiving cisplatin, so that more careful monitoring, dose adjustments, or an alternative treatment, if available, might be considered.
However, previous models were limited by factors such as small sample sizes, lack of external validation, older data, and liberal definitions of AKI, said Shruti Gupta, MD, MPH, director of onco-nephrology at Brigham and Women’s Hospital (BWH) and Dana-Farber Cancer Institute, and David E. Leaf, MD, MMSc, director of clinical and translational research in AKI, Division of Renal Medicine, BWH, Boston.
Dr. Gupta and Dr. Leaf believe their risk score for predicting severe AKI after intravenous (IV) cisplatin, published online in The BMJ, is “more accurate and generalizable than prior models for several reasons,” they told this news organization in a joint email.
“First, we externally validated our findings across cancer centers other than the one where it was developed,” they said. “Second, we focused on moderate to severe kidney injury, the most clinically relevant form of kidney damage, whereas prior models examined more mild forms of kidney injury. Third, we collected data on nearly 25,000 patients receiving their first dose of IV cisplatin, which is larger than all previous studies combined.”
‘Herculean Effort’
“We conceived of this study back in 2018, contacted collaborators at each participating cancer center, and had numerous meetings to try to gather granular data on patients treated with their first dose of intravenous (IV) cisplatin,” Dr. Gupta and Dr. Leaf explained. They also incorporated patient feedback from focus groups and surveys.
“This was truly a Herculean effort that involved physicians, programmers, research coordinators, and patients,” they said.
The multicenter study included 24,717 patients — 11,766 in the derivation cohort and 12,951 in the validation cohort. Overall, the median age was about 60 years, about 58% were men, and about 78% were White.
The primary outcome was cisplatin-induced AKI (CP-AKI), defined as a twofold or greater increase in serum creatinine or kidney replacement therapy within 14 days of a first dose of IV cisplatin.
Their simple risk score consisting of nine covariates — age, hypertension, type 2 diabetes, hemoglobin level, white blood cell count, platelet count, serum albumin level, serum magnesium level, and cisplatin dose — predicted a higher risk for CP-AKI in both cohorts.
Notably, adding serum creatinine to the model did not change the area under the curve, and therefore, serum creatinine, though also an independent risk factor for CP-AKI, was not included in the score.
Patients in the highest risk category had 24-fold higher odds of CP-AKI in the derivation cohort and close to 18-fold higher odds in the validation cohort than those in the lowest risk category.
The primary model had a C statistic of 0.75 (95% CI, 0.73-0.76) and showed better discrimination for CP-AKI than previously published models, for which the C statistics ranged from 0.60 to 0.68. The first author of a paper on an earlier model, Shveta Motwani, MD, MMSc, of BWH and Dana-Farber Cancer Institute in Boston, is also a coauthor of the new study.
Greater severity of CP-AKI was associated with shorter 90-day survival (adjusted hazard ratio, 4.63; 95% CI, 3.56-6.02) for stage III CP-AKI vs no CP-AKI.
‘Definitive Work’
Joel M. Topf, MD, a nephrologist with expertise in chronic kidney disease in Detroit, who wasn’t involved in the development of the risk score, called the study “a definitive work on an important concept in oncology and nephrology.”
“While this is not the first attempt to devise a risk score, it is by far the biggest,” he told this news organization. Furthermore, the authors “used a diverse population, recruiting patients with a variety of cancers (previous attempts had often used a homogenous diagnosis, putting into question how generalizable the results were) from six different cancer centers.”
In addition, he said, “The authors did not restrict patients with chronic kidney disease or other significant comorbidities and used the geographic diversity to produce a cohort that has an age, gender, racial, and ethnic distribution, which is more representative of the US than previous, single-center attempts to risk score patients.”
An earlier model used the Kidney Disease: Improving Global Outcomes (KDIGO) consensus definition of AKI of an increase in serum creatinine of 0.3 mg/dL, he noted. “While a sensitive definition of AKI, it captures mild, hemodynamic increases in creatinine of questionable significance,” he said.
By contrast, the new score uses KDIGO stage II and above to define AKI. “This is a better choice, as we do not want to dissuade patients and doctors from choosing chemotherapy due to a fear of insignificant kidney damage,” he said.
All that said, Dr. Topf noted that neither the current score nor the earlier model included serum creatinine. “This is curious to me and may represent the small number of patients with representative elevated creatinine in the derivation cohort (only 1.3% with an estimated glomerular filtration rate [eGFR] < 45).”
“Since the cohort is made up of people who received cis-platinum, the low prevalence of eGFRs < 45 may be due to physicians steering away from cis-platinum in this group,” he suggested. “It would be unfortunate if this risk score gave an unintentional ‘green light’ to these patients, exposing them to predictable harm.”
‘Certainly Useful’
Anushree Shirali, MD, an associate professor in the Section of Nephrology and consulting physician, Yale Onco-Nephrology, Yale School of Medicine, in New Haven, Connecticut, said that having a prediction score for which patients are more likely to develop AKI after a single dose of cisplatin would be helpful for oncologists, as well as nephrologists.
As a nephrologist, Dr. Shirali mostly sees patients who already have AKI, she told this news organization. But there are circumstances in which the tool could still be helpful.
“Let’s say someone has abnormal kidney function at baseline — ie, creatinine is higher than the normal range — and they were on dialysis 5 years ago for something else, and now, they have cancer and may be given cisplatin. They worry about their chances of getting AKI and needing dialysis again,” she said. “That’s just one scenario in which I might be asked to answer that question and the tool would certainly be useful.”
Other scenarios could include someone who has just one kidney because they donated a kidney for transplant years ago, and now, they have a malignancy and wonder what their actual risk is of getting kidney issues on cisplatin.
Oncologists could use the tool to determine whether a patient should be treated with cisplatin, or if they’re at high risk, whether an alternative that’s not nephrotoxic might be used. By contrast, “if somebody’s low risk and an oncologist thinks cisplatin is the best agent they have, then they might want to go ahead and use it,” Dr. Shirali said.
Future research could take into consideration that CP-AKI is dose dependent, she suggested, because a prediction score that included the number of cisplatin doses could be even more helpful to determine risk. And, even though the derivation and validation cohorts for the new tool are representative of the US population, additional research should also include more racial/ethnic diversity, she said.
Dr. Gupta and Dr. Leaf hope their tool “will be utilized immediately by patients and providers to help predict an individual’s risk of cisplatin-associated kidney damage. It is easy to use, available for free online, and incorporates readily available clinical variables.”
If a patient is at high risk, the clinical team can consider preventive measures such as administering more IV fluids before receiving cisplatin or monitoring kidney function more closely afterward, they suggested.
Dr. Gupta reported research support from the National Institutes of Health (NIH) and the National Institute of Diabetes and Digestive and Kidney Diseases. She also reported research funding from BTG International, GE HealthCare, and AstraZeneca outside the submitted work. She is a member of GlaxoSmithKline’s Global Anemia Council, a consultant for Secretome and Proletariat Therapeutics, and founder and president emeritus of the American Society of Onconephrology (unpaid). Dr. Leaf is supported by NIH grants, reported research support from BioPorto, BTG International, and Metro International Biotech, and has served as a consultant. Dr. Topf reported an ownership stake in a few DaVita-run dialysis clinics. He also runs a vascular access center and has participated in advisory boards with Cara Therapeutics, Vifor, Astra Zeneca, Bayer, Renibus Therapeutics, Travere Therapeutics, and GlaxoSmithKline. He is president of NephJC, a nonprofit educational organization with no industry support. Dr. Shirali declared no competing interests.
A version of this article appeared on Medscape.com.
Cisplatin is a preferred treatment for a wide range of cancers, including breast, head and neck, lung, ovary, and more. However, its side effects — particularly nephrotoxicity — can be severe. Kidney injury on cisplatin is associated with higher mortality and can jeopardize a patient’s eligibility for other therapies.
Now, in a large study using data from six US cancer centers, researchers have developed a risk algorithm to predict acute kidney injury (AKI) after cisplatin administration.
A risk prediction calculator based on the algorithm is available online for patients and providers to determine an individual patient›s risk for kidney injury from cisplatin using readily available clinical data.
Other risk scores and risk prediction models have been developed to help clinicians assess in advance whether a patient might develop AKI after receiving cisplatin, so that more careful monitoring, dose adjustments, or an alternative treatment, if available, might be considered.
However, previous models were limited by factors such as small sample sizes, lack of external validation, older data, and liberal definitions of AKI, said Shruti Gupta, MD, MPH, director of onco-nephrology at Brigham and Women’s Hospital (BWH) and Dana-Farber Cancer Institute, and David E. Leaf, MD, MMSc, director of clinical and translational research in AKI, Division of Renal Medicine, BWH, Boston.
Dr. Gupta and Dr. Leaf believe their risk score for predicting severe AKI after intravenous (IV) cisplatin, published online in The BMJ, is “more accurate and generalizable than prior models for several reasons,” they told this news organization in a joint email.
“First, we externally validated our findings across cancer centers other than the one where it was developed,” they said. “Second, we focused on moderate to severe kidney injury, the most clinically relevant form of kidney damage, whereas prior models examined more mild forms of kidney injury. Third, we collected data on nearly 25,000 patients receiving their first dose of IV cisplatin, which is larger than all previous studies combined.”
‘Herculean Effort’
“We conceived of this study back in 2018, contacted collaborators at each participating cancer center, and had numerous meetings to try to gather granular data on patients treated with their first dose of intravenous (IV) cisplatin,” Dr. Gupta and Dr. Leaf explained. They also incorporated patient feedback from focus groups and surveys.
“This was truly a Herculean effort that involved physicians, programmers, research coordinators, and patients,” they said.
The multicenter study included 24,717 patients — 11,766 in the derivation cohort and 12,951 in the validation cohort. Overall, the median age was about 60 years, about 58% were men, and about 78% were White.
The primary outcome was cisplatin-induced AKI (CP-AKI), defined as a twofold or greater increase in serum creatinine or kidney replacement therapy within 14 days of a first dose of IV cisplatin.
Their simple risk score consisting of nine covariates — age, hypertension, type 2 diabetes, hemoglobin level, white blood cell count, platelet count, serum albumin level, serum magnesium level, and cisplatin dose — predicted a higher risk for CP-AKI in both cohorts.
Notably, adding serum creatinine to the model did not change the area under the curve, and therefore, serum creatinine, though also an independent risk factor for CP-AKI, was not included in the score.
Patients in the highest risk category had 24-fold higher odds of CP-AKI in the derivation cohort and close to 18-fold higher odds in the validation cohort than those in the lowest risk category.
The primary model had a C statistic of 0.75 (95% CI, 0.73-0.76) and showed better discrimination for CP-AKI than previously published models, for which the C statistics ranged from 0.60 to 0.68. The first author of a paper on an earlier model, Shveta Motwani, MD, MMSc, of BWH and Dana-Farber Cancer Institute in Boston, is also a coauthor of the new study.
Greater severity of CP-AKI was associated with shorter 90-day survival (adjusted hazard ratio, 4.63; 95% CI, 3.56-6.02) for stage III CP-AKI vs no CP-AKI.
‘Definitive Work’
Joel M. Topf, MD, a nephrologist with expertise in chronic kidney disease in Detroit, who wasn’t involved in the development of the risk score, called the study “a definitive work on an important concept in oncology and nephrology.”
“While this is not the first attempt to devise a risk score, it is by far the biggest,” he told this news organization. Furthermore, the authors “used a diverse population, recruiting patients with a variety of cancers (previous attempts had often used a homogenous diagnosis, putting into question how generalizable the results were) from six different cancer centers.”
In addition, he said, “The authors did not restrict patients with chronic kidney disease or other significant comorbidities and used the geographic diversity to produce a cohort that has an age, gender, racial, and ethnic distribution, which is more representative of the US than previous, single-center attempts to risk score patients.”
An earlier model used the Kidney Disease: Improving Global Outcomes (KDIGO) consensus definition of AKI of an increase in serum creatinine of 0.3 mg/dL, he noted. “While a sensitive definition of AKI, it captures mild, hemodynamic increases in creatinine of questionable significance,” he said.
By contrast, the new score uses KDIGO stage II and above to define AKI. “This is a better choice, as we do not want to dissuade patients and doctors from choosing chemotherapy due to a fear of insignificant kidney damage,” he said.
All that said, Dr. Topf noted that neither the current score nor the earlier model included serum creatinine. “This is curious to me and may represent the small number of patients with representative elevated creatinine in the derivation cohort (only 1.3% with an estimated glomerular filtration rate [eGFR] < 45).”
“Since the cohort is made up of people who received cis-platinum, the low prevalence of eGFRs < 45 may be due to physicians steering away from cis-platinum in this group,” he suggested. “It would be unfortunate if this risk score gave an unintentional ‘green light’ to these patients, exposing them to predictable harm.”
‘Certainly Useful’
Anushree Shirali, MD, an associate professor in the Section of Nephrology and consulting physician, Yale Onco-Nephrology, Yale School of Medicine, in New Haven, Connecticut, said that having a prediction score for which patients are more likely to develop AKI after a single dose of cisplatin would be helpful for oncologists, as well as nephrologists.
As a nephrologist, Dr. Shirali mostly sees patients who already have AKI, she told this news organization. But there are circumstances in which the tool could still be helpful.
“Let’s say someone has abnormal kidney function at baseline — ie, creatinine is higher than the normal range — and they were on dialysis 5 years ago for something else, and now, they have cancer and may be given cisplatin. They worry about their chances of getting AKI and needing dialysis again,” she said. “That’s just one scenario in which I might be asked to answer that question and the tool would certainly be useful.”
Other scenarios could include someone who has just one kidney because they donated a kidney for transplant years ago, and now, they have a malignancy and wonder what their actual risk is of getting kidney issues on cisplatin.
Oncologists could use the tool to determine whether a patient should be treated with cisplatin, or if they’re at high risk, whether an alternative that’s not nephrotoxic might be used. By contrast, “if somebody’s low risk and an oncologist thinks cisplatin is the best agent they have, then they might want to go ahead and use it,” Dr. Shirali said.
Future research could take into consideration that CP-AKI is dose dependent, she suggested, because a prediction score that included the number of cisplatin doses could be even more helpful to determine risk. And, even though the derivation and validation cohorts for the new tool are representative of the US population, additional research should also include more racial/ethnic diversity, she said.
Dr. Gupta and Dr. Leaf hope their tool “will be utilized immediately by patients and providers to help predict an individual’s risk of cisplatin-associated kidney damage. It is easy to use, available for free online, and incorporates readily available clinical variables.”
If a patient is at high risk, the clinical team can consider preventive measures such as administering more IV fluids before receiving cisplatin or monitoring kidney function more closely afterward, they suggested.
Dr. Gupta reported research support from the National Institutes of Health (NIH) and the National Institute of Diabetes and Digestive and Kidney Diseases. She also reported research funding from BTG International, GE HealthCare, and AstraZeneca outside the submitted work. She is a member of GlaxoSmithKline’s Global Anemia Council, a consultant for Secretome and Proletariat Therapeutics, and founder and president emeritus of the American Society of Onconephrology (unpaid). Dr. Leaf is supported by NIH grants, reported research support from BioPorto, BTG International, and Metro International Biotech, and has served as a consultant. Dr. Topf reported an ownership stake in a few DaVita-run dialysis clinics. He also runs a vascular access center and has participated in advisory boards with Cara Therapeutics, Vifor, Astra Zeneca, Bayer, Renibus Therapeutics, Travere Therapeutics, and GlaxoSmithKline. He is president of NephJC, a nonprofit educational organization with no industry support. Dr. Shirali declared no competing interests.
A version of this article appeared on Medscape.com.
FROM THE BMJ
Can Nectin-4 Expression Predict Response to Bladder Cancer Treatment?
Identifying biomarkers to predict how patients will respond to targeted therapies is crucial to improve treatments for patients with cancer, authors Niklas Klümper, MD, with the Department of Urology and Pediatric Urology at University Hospital Bonn, in Germany, and colleagues, wrote in the Journal of Clinical Oncology (doi: 10.1200/JCO.23.01983).
The researchers used a Nectin-4-specific fluorescence in situ hybridization (FISH) assay in an (m)UC cohort of 108 patients to test Nectin-4’s ability to predict responses, analyzing slides with a fluorescence microscope. The copy number variations (CNVs) were correlated with membranous Nectin-4 protein expression, responses to EV treatment, and outcomes.
They also evaluated the prognostic value of Nectin-4 CNVs with biopsies of 103 (m)UC patients not treated with EV. Additionally, they searched The Cancer Genome Atlas (TCGA) data sets (10,712 patients across 32 cancer types) for Nectin-4 CNVs.
Why Was This Study Done?
Urothelial carcinoma accounts for 90% of bladder cancer cases globally. Though EV was approved to treat (m)UC in 2019, lasting benefit has been achieved only in a small subset of patients.
EV is given to all without selecting patients based on biomarkers that may predict how well they will respond to EV. In this study, researchers investigated whether response to EV was better when people had amplification — defined as increased numbers of copies — of Nectin-4.
How Common Is It for Patients With (m)UC to Have Nectin-4 Amplifications?
Nectin-4 amplifications happen frequently in (m)UC; they occurred in about 26% of the (m)UC patients the researchers studied, according to the new paper.
The amplifications are frequent in other cancer types as well, and this study suggests that this biomarker is a promising candidate for developing Nectin-4–targeted antibody-drug conjugates for other cancers.
“Nectin-4 amplifications can be found in 5%-10% of breast cancer and non–small cell lung cancer, both tumor types with a high impact on all-cancer mortality, which are currently being evaluated for EV response,” the authors wrote.
Currently, (m)UC is the only cancer for which EV is approved as standard-of-care, the researchers explain, in their paper.
What Were the Differences Between the EV and Non-EV Groups?
Almost all (27 of the 28) patients in the cohort (96%) who had Nectin-4 amplifications had objective responses to EV compared with 24 of 74 (32%) in the group without amplifications (P less than .001). Among the 96% with a response, 82% had partial response and 14% had a complete response.
The amplifications for those treated with EV were linked with longer progression-free survival (90% 12-month PFS vs 41% for those with nonamplified tumors) and longer overall survival (OS).
For those patients treated with EV who had the amplifications, OS was not reached. This was because the researchers could not calculate the OS at 12 months for this group due to more than half of the patients still being alive at that time. That finding contrasts with a median OS of 8.8 months in those patients treated with EV who did not have the amplifications.
EV-treated patients who had Nectin-4 amplifications had a 92% lower risk of death compared with EV-treated patients without the amplifications, according to an analysis that adjusted for factors including age and sex.
“Importantly, in the non–EV-treated patients with (m)UC, Nectin-4 amplifications have no impact on OS [overall survival], suggesting that Nectin-4 amplifications are neither indicating aggressive nor favorable tumor biology, strengthening its potential value as a pure predictive biomarker,” the researchers wrote.
What Are the Implications of These Findings?
“[O]ur study suggests that Nectin-4 amplification is a simple, valuable, and easy-to-implement predictive biomarker for EV in patients with (m)UC. The frequent occurrence of Nectin-4 amplifications in other cancer types suggests that this biomarker is a promising candidate with broader applicability for clinical development of Nectin-4-targeted ADCs in a tumor-agnostic context.”
Choosing the best therapy sequence for (m)UC is crucial, the authors write. Considering Nectin-4 amplifications could inform EV drug development — even at earlier stages of the disease — by defining which patient subgroup has the highest chance for long-term benefit.
The authors acknowledge that the primary limitation of the study is that it is retrospective, using archived primary and metastatic tumor specimens with varying ranges between the time of tumor sampling and start of EV treatment.
“Therefore, our data are hypothesis-generating and prospective confirmation in larger, biomarker-driven trials is mandatory,” the authors wrote.
They note that EV plus pembrolizumab [Keytruda] (EV/P) was recently approved as the new standard of care in first-line treatment for (m)UC, so the predictive value of Nectin-4 amplification in this new treatment setting warrants further research.
Dr. Klümper reports stock and other ownership interests in Bicycle Therapeutics, Pfizer, Daiichi Sankyo/UCB Japan, and Immatics; and honoraria for Astellas Pharma and MSD Oncology; and consulting or advisory roles with Astellas Pharma, MSD Oncology, and Eisai. He reports travel reimbursements from Ipsen, Photocure, and MSD Oncology. Other author disclosures are available with the full text of the paper.
Identifying biomarkers to predict how patients will respond to targeted therapies is crucial to improve treatments for patients with cancer, authors Niklas Klümper, MD, with the Department of Urology and Pediatric Urology at University Hospital Bonn, in Germany, and colleagues, wrote in the Journal of Clinical Oncology (doi: 10.1200/JCO.23.01983).
The researchers used a Nectin-4-specific fluorescence in situ hybridization (FISH) assay in an (m)UC cohort of 108 patients to test Nectin-4’s ability to predict responses, analyzing slides with a fluorescence microscope. The copy number variations (CNVs) were correlated with membranous Nectin-4 protein expression, responses to EV treatment, and outcomes.
They also evaluated the prognostic value of Nectin-4 CNVs with biopsies of 103 (m)UC patients not treated with EV. Additionally, they searched The Cancer Genome Atlas (TCGA) data sets (10,712 patients across 32 cancer types) for Nectin-4 CNVs.
Why Was This Study Done?
Urothelial carcinoma accounts for 90% of bladder cancer cases globally. Though EV was approved to treat (m)UC in 2019, lasting benefit has been achieved only in a small subset of patients.
EV is given to all without selecting patients based on biomarkers that may predict how well they will respond to EV. In this study, researchers investigated whether response to EV was better when people had amplification — defined as increased numbers of copies — of Nectin-4.
How Common Is It for Patients With (m)UC to Have Nectin-4 Amplifications?
Nectin-4 amplifications happen frequently in (m)UC; they occurred in about 26% of the (m)UC patients the researchers studied, according to the new paper.
The amplifications are frequent in other cancer types as well, and this study suggests that this biomarker is a promising candidate for developing Nectin-4–targeted antibody-drug conjugates for other cancers.
“Nectin-4 amplifications can be found in 5%-10% of breast cancer and non–small cell lung cancer, both tumor types with a high impact on all-cancer mortality, which are currently being evaluated for EV response,” the authors wrote.
Currently, (m)UC is the only cancer for which EV is approved as standard-of-care, the researchers explain, in their paper.
What Were the Differences Between the EV and Non-EV Groups?
Almost all (27 of the 28) patients in the cohort (96%) who had Nectin-4 amplifications had objective responses to EV compared with 24 of 74 (32%) in the group without amplifications (P less than .001). Among the 96% with a response, 82% had partial response and 14% had a complete response.
The amplifications for those treated with EV were linked with longer progression-free survival (90% 12-month PFS vs 41% for those with nonamplified tumors) and longer overall survival (OS).
For those patients treated with EV who had the amplifications, OS was not reached. This was because the researchers could not calculate the OS at 12 months for this group due to more than half of the patients still being alive at that time. That finding contrasts with a median OS of 8.8 months in those patients treated with EV who did not have the amplifications.
EV-treated patients who had Nectin-4 amplifications had a 92% lower risk of death compared with EV-treated patients without the amplifications, according to an analysis that adjusted for factors including age and sex.
“Importantly, in the non–EV-treated patients with (m)UC, Nectin-4 amplifications have no impact on OS [overall survival], suggesting that Nectin-4 amplifications are neither indicating aggressive nor favorable tumor biology, strengthening its potential value as a pure predictive biomarker,” the researchers wrote.
What Are the Implications of These Findings?
“[O]ur study suggests that Nectin-4 amplification is a simple, valuable, and easy-to-implement predictive biomarker for EV in patients with (m)UC. The frequent occurrence of Nectin-4 amplifications in other cancer types suggests that this biomarker is a promising candidate with broader applicability for clinical development of Nectin-4-targeted ADCs in a tumor-agnostic context.”
Choosing the best therapy sequence for (m)UC is crucial, the authors write. Considering Nectin-4 amplifications could inform EV drug development — even at earlier stages of the disease — by defining which patient subgroup has the highest chance for long-term benefit.
The authors acknowledge that the primary limitation of the study is that it is retrospective, using archived primary and metastatic tumor specimens with varying ranges between the time of tumor sampling and start of EV treatment.
“Therefore, our data are hypothesis-generating and prospective confirmation in larger, biomarker-driven trials is mandatory,” the authors wrote.
They note that EV plus pembrolizumab [Keytruda] (EV/P) was recently approved as the new standard of care in first-line treatment for (m)UC, so the predictive value of Nectin-4 amplification in this new treatment setting warrants further research.
Dr. Klümper reports stock and other ownership interests in Bicycle Therapeutics, Pfizer, Daiichi Sankyo/UCB Japan, and Immatics; and honoraria for Astellas Pharma and MSD Oncology; and consulting or advisory roles with Astellas Pharma, MSD Oncology, and Eisai. He reports travel reimbursements from Ipsen, Photocure, and MSD Oncology. Other author disclosures are available with the full text of the paper.
Identifying biomarkers to predict how patients will respond to targeted therapies is crucial to improve treatments for patients with cancer, authors Niklas Klümper, MD, with the Department of Urology and Pediatric Urology at University Hospital Bonn, in Germany, and colleagues, wrote in the Journal of Clinical Oncology (doi: 10.1200/JCO.23.01983).
The researchers used a Nectin-4-specific fluorescence in situ hybridization (FISH) assay in an (m)UC cohort of 108 patients to test Nectin-4’s ability to predict responses, analyzing slides with a fluorescence microscope. The copy number variations (CNVs) were correlated with membranous Nectin-4 protein expression, responses to EV treatment, and outcomes.
They also evaluated the prognostic value of Nectin-4 CNVs with biopsies of 103 (m)UC patients not treated with EV. Additionally, they searched The Cancer Genome Atlas (TCGA) data sets (10,712 patients across 32 cancer types) for Nectin-4 CNVs.
Why Was This Study Done?
Urothelial carcinoma accounts for 90% of bladder cancer cases globally. Though EV was approved to treat (m)UC in 2019, lasting benefit has been achieved only in a small subset of patients.
EV is given to all without selecting patients based on biomarkers that may predict how well they will respond to EV. In this study, researchers investigated whether response to EV was better when people had amplification — defined as increased numbers of copies — of Nectin-4.
How Common Is It for Patients With (m)UC to Have Nectin-4 Amplifications?
Nectin-4 amplifications happen frequently in (m)UC; they occurred in about 26% of the (m)UC patients the researchers studied, according to the new paper.
The amplifications are frequent in other cancer types as well, and this study suggests that this biomarker is a promising candidate for developing Nectin-4–targeted antibody-drug conjugates for other cancers.
“Nectin-4 amplifications can be found in 5%-10% of breast cancer and non–small cell lung cancer, both tumor types with a high impact on all-cancer mortality, which are currently being evaluated for EV response,” the authors wrote.
Currently, (m)UC is the only cancer for which EV is approved as standard-of-care, the researchers explain, in their paper.
What Were the Differences Between the EV and Non-EV Groups?
Almost all (27 of the 28) patients in the cohort (96%) who had Nectin-4 amplifications had objective responses to EV compared with 24 of 74 (32%) in the group without amplifications (P less than .001). Among the 96% with a response, 82% had partial response and 14% had a complete response.
The amplifications for those treated with EV were linked with longer progression-free survival (90% 12-month PFS vs 41% for those with nonamplified tumors) and longer overall survival (OS).
For those patients treated with EV who had the amplifications, OS was not reached. This was because the researchers could not calculate the OS at 12 months for this group due to more than half of the patients still being alive at that time. That finding contrasts with a median OS of 8.8 months in those patients treated with EV who did not have the amplifications.
EV-treated patients who had Nectin-4 amplifications had a 92% lower risk of death compared with EV-treated patients without the amplifications, according to an analysis that adjusted for factors including age and sex.
“Importantly, in the non–EV-treated patients with (m)UC, Nectin-4 amplifications have no impact on OS [overall survival], suggesting that Nectin-4 amplifications are neither indicating aggressive nor favorable tumor biology, strengthening its potential value as a pure predictive biomarker,” the researchers wrote.
What Are the Implications of These Findings?
“[O]ur study suggests that Nectin-4 amplification is a simple, valuable, and easy-to-implement predictive biomarker for EV in patients with (m)UC. The frequent occurrence of Nectin-4 amplifications in other cancer types suggests that this biomarker is a promising candidate with broader applicability for clinical development of Nectin-4-targeted ADCs in a tumor-agnostic context.”
Choosing the best therapy sequence for (m)UC is crucial, the authors write. Considering Nectin-4 amplifications could inform EV drug development — even at earlier stages of the disease — by defining which patient subgroup has the highest chance for long-term benefit.
The authors acknowledge that the primary limitation of the study is that it is retrospective, using archived primary and metastatic tumor specimens with varying ranges between the time of tumor sampling and start of EV treatment.
“Therefore, our data are hypothesis-generating and prospective confirmation in larger, biomarker-driven trials is mandatory,” the authors wrote.
They note that EV plus pembrolizumab [Keytruda] (EV/P) was recently approved as the new standard of care in first-line treatment for (m)UC, so the predictive value of Nectin-4 amplification in this new treatment setting warrants further research.
Dr. Klümper reports stock and other ownership interests in Bicycle Therapeutics, Pfizer, Daiichi Sankyo/UCB Japan, and Immatics; and honoraria for Astellas Pharma and MSD Oncology; and consulting or advisory roles with Astellas Pharma, MSD Oncology, and Eisai. He reports travel reimbursements from Ipsen, Photocure, and MSD Oncology. Other author disclosures are available with the full text of the paper.
FROM JOURNAL OF CLINICAL ONCOLOGY
Do Patients Benefit from Cancer Trial Participation?
TOPLINE:
METHODOLOGY:
- The view that patients with cancer benefit from access to investigational drugs in the clinical trial setting is widely held but does necessarily align with trial findings, which often show limited evidence of a clinical benefit. First, most investigational treatments assessed in clinical trials fail to gain regulatory approval, and the minority that are approved tend to offer minimal clinical benefit, experts explained.
- To estimate the survival benefit and toxicities associated with receiving experimental treatments, researchers conducted a meta-analysis of 128 trials comprising 141 comparisons of an investigational drug and a control treatment, which included immunotherapies and targeted therapies.
- The analysis included 42 trials in non–small cell lung cancer (NSCLC), 37 in breast cancer, 15 in hepatobiliary cancer, 13 in pancreatic cancer, 12 in colorectal cancer, and 10 in prostate cancer, involving a total of 47,050 patients.
- The primary outcome was PFS and secondary outcomes were overall survival and grades 3-5 serious adverse events.
TAKEAWAY:
- Overall, the experimental treatment was associated with a 20% improvement in PFS (pooled hazard ratio [HR], 0.80), corresponding to a median 1.25-month PFS advantage. The PFS benefit was seen across all cancer types, except pancreatic cancer.
- Overall survival improved by 8% with experimental agents (HR, 0.92), corresponding to 1.18 additional months. A significant overall survival benefit was seen across NSCLC, breast cancer, and hepatobiliary cancer trials but not pancreatic, prostate, colorectal cancer trials.
- Patients in the experimental intervention group, however, experienced much higher risk for grade 3-5 serious adverse events (risk ratio [RR], 1.27), corresponding to 7.40% increase in absolute risk. The greater risk for serious adverse events was significant for all indications except prostate cancer (RR, 1.13; 95% CI, 0.91-1.40).
IN PRACTICE:
“We believe our findings are best interpreted as suggesting that access to experimental interventions that have not yet received full FDA approval is associated with a marginal but nonzero clinical benefit,” the authors wrote.
“Although our findings seem to reflect poorly on trials as a vehicle for extending survival for participants, they have reassuring implications for clinical investigators, policymakers, and institutional review boards,” the researchers said, explaining that this “scenario allows clinical trials to continue to pursue promising new treatments — supporting incremental advances that sum to large gains over extended periods of research — without disadvantaging patients in comparator groups.”
SOURCE:
Renata Iskander, MSc, of McGill University, Montreal, Quebec, Canada, led this work, which was published online on April 29, 2024, in Annals of Internal Medicine.
LIMITATIONS:
There was high heterogeneity across studies due to variations in drugs tested, comparators used, and populations involved. The use of comparators below standard care could have inflated survival benefits. Additionally, data collected from ClinicalTrials.gov might be biased due to some trials not being reported.
DISCLOSURES:
Canadian Institutes of Health Research supported this work. The authors received grants for this work from McGill University, Rossy Cancer Network, and National Science Foundation. One author received consulting fees outside this work. The other authors declared no competing interests.
A version of this article appeared on Medscape.com.
TOPLINE:
METHODOLOGY:
- The view that patients with cancer benefit from access to investigational drugs in the clinical trial setting is widely held but does necessarily align with trial findings, which often show limited evidence of a clinical benefit. First, most investigational treatments assessed in clinical trials fail to gain regulatory approval, and the minority that are approved tend to offer minimal clinical benefit, experts explained.
- To estimate the survival benefit and toxicities associated with receiving experimental treatments, researchers conducted a meta-analysis of 128 trials comprising 141 comparisons of an investigational drug and a control treatment, which included immunotherapies and targeted therapies.
- The analysis included 42 trials in non–small cell lung cancer (NSCLC), 37 in breast cancer, 15 in hepatobiliary cancer, 13 in pancreatic cancer, 12 in colorectal cancer, and 10 in prostate cancer, involving a total of 47,050 patients.
- The primary outcome was PFS and secondary outcomes were overall survival and grades 3-5 serious adverse events.
TAKEAWAY:
- Overall, the experimental treatment was associated with a 20% improvement in PFS (pooled hazard ratio [HR], 0.80), corresponding to a median 1.25-month PFS advantage. The PFS benefit was seen across all cancer types, except pancreatic cancer.
- Overall survival improved by 8% with experimental agents (HR, 0.92), corresponding to 1.18 additional months. A significant overall survival benefit was seen across NSCLC, breast cancer, and hepatobiliary cancer trials but not pancreatic, prostate, colorectal cancer trials.
- Patients in the experimental intervention group, however, experienced much higher risk for grade 3-5 serious adverse events (risk ratio [RR], 1.27), corresponding to 7.40% increase in absolute risk. The greater risk for serious adverse events was significant for all indications except prostate cancer (RR, 1.13; 95% CI, 0.91-1.40).
IN PRACTICE:
“We believe our findings are best interpreted as suggesting that access to experimental interventions that have not yet received full FDA approval is associated with a marginal but nonzero clinical benefit,” the authors wrote.
“Although our findings seem to reflect poorly on trials as a vehicle for extending survival for participants, they have reassuring implications for clinical investigators, policymakers, and institutional review boards,” the researchers said, explaining that this “scenario allows clinical trials to continue to pursue promising new treatments — supporting incremental advances that sum to large gains over extended periods of research — without disadvantaging patients in comparator groups.”
SOURCE:
Renata Iskander, MSc, of McGill University, Montreal, Quebec, Canada, led this work, which was published online on April 29, 2024, in Annals of Internal Medicine.
LIMITATIONS:
There was high heterogeneity across studies due to variations in drugs tested, comparators used, and populations involved. The use of comparators below standard care could have inflated survival benefits. Additionally, data collected from ClinicalTrials.gov might be biased due to some trials not being reported.
DISCLOSURES:
Canadian Institutes of Health Research supported this work. The authors received grants for this work from McGill University, Rossy Cancer Network, and National Science Foundation. One author received consulting fees outside this work. The other authors declared no competing interests.
A version of this article appeared on Medscape.com.
TOPLINE:
METHODOLOGY:
- The view that patients with cancer benefit from access to investigational drugs in the clinical trial setting is widely held but does necessarily align with trial findings, which often show limited evidence of a clinical benefit. First, most investigational treatments assessed in clinical trials fail to gain regulatory approval, and the minority that are approved tend to offer minimal clinical benefit, experts explained.
- To estimate the survival benefit and toxicities associated with receiving experimental treatments, researchers conducted a meta-analysis of 128 trials comprising 141 comparisons of an investigational drug and a control treatment, which included immunotherapies and targeted therapies.
- The analysis included 42 trials in non–small cell lung cancer (NSCLC), 37 in breast cancer, 15 in hepatobiliary cancer, 13 in pancreatic cancer, 12 in colorectal cancer, and 10 in prostate cancer, involving a total of 47,050 patients.
- The primary outcome was PFS and secondary outcomes were overall survival and grades 3-5 serious adverse events.
TAKEAWAY:
- Overall, the experimental treatment was associated with a 20% improvement in PFS (pooled hazard ratio [HR], 0.80), corresponding to a median 1.25-month PFS advantage. The PFS benefit was seen across all cancer types, except pancreatic cancer.
- Overall survival improved by 8% with experimental agents (HR, 0.92), corresponding to 1.18 additional months. A significant overall survival benefit was seen across NSCLC, breast cancer, and hepatobiliary cancer trials but not pancreatic, prostate, colorectal cancer trials.
- Patients in the experimental intervention group, however, experienced much higher risk for grade 3-5 serious adverse events (risk ratio [RR], 1.27), corresponding to 7.40% increase in absolute risk. The greater risk for serious adverse events was significant for all indications except prostate cancer (RR, 1.13; 95% CI, 0.91-1.40).
IN PRACTICE:
“We believe our findings are best interpreted as suggesting that access to experimental interventions that have not yet received full FDA approval is associated with a marginal but nonzero clinical benefit,” the authors wrote.
“Although our findings seem to reflect poorly on trials as a vehicle for extending survival for participants, they have reassuring implications for clinical investigators, policymakers, and institutional review boards,” the researchers said, explaining that this “scenario allows clinical trials to continue to pursue promising new treatments — supporting incremental advances that sum to large gains over extended periods of research — without disadvantaging patients in comparator groups.”
SOURCE:
Renata Iskander, MSc, of McGill University, Montreal, Quebec, Canada, led this work, which was published online on April 29, 2024, in Annals of Internal Medicine.
LIMITATIONS:
There was high heterogeneity across studies due to variations in drugs tested, comparators used, and populations involved. The use of comparators below standard care could have inflated survival benefits. Additionally, data collected from ClinicalTrials.gov might be biased due to some trials not being reported.
DISCLOSURES:
Canadian Institutes of Health Research supported this work. The authors received grants for this work from McGill University, Rossy Cancer Network, and National Science Foundation. One author received consulting fees outside this work. The other authors declared no competing interests.
A version of this article appeared on Medscape.com.
Do Health-Related Social Needs Raise Mortality Risk in Cancer Survivors?
Little is known about the specific association between health-related social needs (HRSNs) and mortality risk even though HRSNs, defined as challenges in affording food, housing, and other necessities of daily living, are potential challenges for cancer survivors, wrote Zhiyuan Zheng, PhD, of the American Cancer Society, Atlanta, and colleagues.
A 2020 study by Dr. Zheng and colleagues published in the Journal of the National Comprehensive Cancer Network (NCCN) showed that food insecurity and financial worries had a negative impact on cancer survivorship. In the new study, published in Cancer, the researchers identified cancer survivors using the 2013-2018 National Health Interview Survey (NHIS) and the NHIS Mortality File through December 31, 2019. The researchers examined mortality using the data from the Centers for Disease Control and Prevention’s National Death Index (NDI) through December 31, 2019, which links to the National Health Interview Survey Data used in the study.
Individuals’ HRSNs were categorized into three groups: severe, moderate, and minor/none. HRSNs included food insecurity and nonmedical financial concerns, such as housing costs (rent, mortgage). Medical financial hardship included material, psychological, and behavioral domains and was divided into three groups: 2-3 domains, 1 domain, or 0 domains.
What Are the Potential Financial Implications of this Research?
The high costs of cancer care often cause medical financial hardships for cancer survivors, and expenses also may cause psychological distress and nonmedical financial hardship as survivors try to make ends meet while facing medical bills, wrote Dr. Zheng and colleagues.
Policy makers are increasingly interested in adding HRSNs to insurance coverage; recent guidance from the Centers for Medicare & Medicaid Services (CMS) allows individual states to apply to provide nutrition and housing supports through state Medicaid programs, according to authors of a 2023 article published in JAMA Health Forum.
The new study adds to the understanding of how HRSNs impact people with cancer by examining the association with mortality risk, Yelak Biru, MSc, president and chief executive officer of the International Myeloma Foundation, said in an interview.
“This is a key area of study for addressing the disparities in treatments and outcomes that result in inequities,” said Mr. Biru, a patient advocate and multiple myeloma survivor who was not involved in the study.
What Does the New Study Show?
The new study characterized HRSNs in 5,855 adult cancer survivors aged 18-64 years and 5,918 aged 65-79 years. In the 18- to 64-year-old group, 25.5% reported moderate levels of HRSNs, and 18.3% reported severe HRSNs. In patients aged 65-79 years, 15.6% and 6.6% reported moderate HRSNs and severe HRSNs, respectively.
Severe HRSN was significantly associated with higher mortality risk in an adjusted analysis in patients aged 18-64 years (hazard ratio 2.00, P < .001).
Among adults aged 65-79 years, severe HRSN was not associated with higher mortality risk; however, in this older age group, those with 2-3 domains of medical financial hardship had significantly increased mortality risk compared with adults aged 65-79 years with zero domains of medical financial hardship (HR 1.58, P = .007).
Although the findings that HRSNs were associated with increased mortality risk, especially in the younger group, were not surprising, they serve as a call to action to address how HRSNs are contributing to cancer mortality, Mr. Biru said in an interview. “HRSNs, like food or housing insecurity, can lead to patients being unable to undergo the best treatment approach for their cancer,” he said.
What Are the Limitations and Research Gaps?
The study findings were limited by several factors including the use of self-reports to measure medical financial hardship, food insecurity, and nonmedical financial concerns in the NHIS, the researchers wrote in their discussion. More research with longer follow-up time beyond 1-5 years is needed, wrote Dr. Zheng and colleagues.
Studies also are needed to illustrate how patient navigation can help prevent patients from falling through the cracks with regard to social needs and financial hardships, Mr. Biru told this news organization.
Other areas for research include how addressing social needs affects health outcomes and whether programs designed to address social needs are effective, he said.
“Finally, qualitative research is needed to capture the lived experiences of cancer survivors facing these challenges. This knowledge can inform the development of more patient-centered interventions and policies that effectively address the social determinants of health and improve overall outcomes for all cancer survivors,” Mr. Biru said.
What Is the Takeaway Message for Clinicians?
HRSNs and financial hardship are significantly associated with increased risk of mortality in adult cancer survivors, Dr. Zheng and colleagues concluded. Looking ahead, comprehensive assessment of HRSNs and financial hardship may help clinicians connect patients with relevant services to mitigate the social and financial impacts of cancer, they wrote.
“The takeaway message for oncologists in practice is that addressing [HRSNs] and financial hardship is crucial for providing comprehensive and equitable cancer care,” Mr. Biru said during his interview.
“The impact of social determinants of health on cancer outcomes cannot be ignored, and oncologists play a vital role in identifying and addressing these needs,” he said. Sensitive, discussion-based screenings are needed to identify core needs such as food and transportation, but clinicians also can consider broader social factors and work with a team to connect patients to appropriate resources, he added.
“By recognizing the importance of HRSN screening and taking proactive steps to address these needs, oncologists can contribute to improving health outcomes, reducing healthcare disparities, and providing more equitable cancer care for their patients,” he said.
What Other Guidance Is Available?
“High-quality cancer care requires treating the whole person; measuring and addressing anything in their life that could result in poorer health outcomes is a key component of comprehensive care,” Mr. Biru emphasized.
In September 2023, the National Comprehensive Cancer Network (NCCN) convened a working group cochaired by Mr. Biru that developed recommendations for how oncology practices should routinely measure HRSNs (NCCN.org/social-needs).
“The working group proposed that every cancer patient be assessed for food, transportation access, and financial and housing security at least once a year, and be reassessed at every care transition point as well,” Mr. Biru said. Such screenings should include follow-up to connect patients with services to address any HRSNs they are experiencing, he added.
Lead author Dr. Zheng is employed by the American Cancer Society, which as a nonprofit receives funds from the public through fundraising and contributions, as well as some support from corporations and industry to support its mission programs and services. Mr. Biru had no financial conflicts to disclose.
Little is known about the specific association between health-related social needs (HRSNs) and mortality risk even though HRSNs, defined as challenges in affording food, housing, and other necessities of daily living, are potential challenges for cancer survivors, wrote Zhiyuan Zheng, PhD, of the American Cancer Society, Atlanta, and colleagues.
A 2020 study by Dr. Zheng and colleagues published in the Journal of the National Comprehensive Cancer Network (NCCN) showed that food insecurity and financial worries had a negative impact on cancer survivorship. In the new study, published in Cancer, the researchers identified cancer survivors using the 2013-2018 National Health Interview Survey (NHIS) and the NHIS Mortality File through December 31, 2019. The researchers examined mortality using the data from the Centers for Disease Control and Prevention’s National Death Index (NDI) through December 31, 2019, which links to the National Health Interview Survey Data used in the study.
Individuals’ HRSNs were categorized into three groups: severe, moderate, and minor/none. HRSNs included food insecurity and nonmedical financial concerns, such as housing costs (rent, mortgage). Medical financial hardship included material, psychological, and behavioral domains and was divided into three groups: 2-3 domains, 1 domain, or 0 domains.
What Are the Potential Financial Implications of this Research?
The high costs of cancer care often cause medical financial hardships for cancer survivors, and expenses also may cause psychological distress and nonmedical financial hardship as survivors try to make ends meet while facing medical bills, wrote Dr. Zheng and colleagues.
Policy makers are increasingly interested in adding HRSNs to insurance coverage; recent guidance from the Centers for Medicare & Medicaid Services (CMS) allows individual states to apply to provide nutrition and housing supports through state Medicaid programs, according to authors of a 2023 article published in JAMA Health Forum.
The new study adds to the understanding of how HRSNs impact people with cancer by examining the association with mortality risk, Yelak Biru, MSc, president and chief executive officer of the International Myeloma Foundation, said in an interview.
“This is a key area of study for addressing the disparities in treatments and outcomes that result in inequities,” said Mr. Biru, a patient advocate and multiple myeloma survivor who was not involved in the study.
What Does the New Study Show?
The new study characterized HRSNs in 5,855 adult cancer survivors aged 18-64 years and 5,918 aged 65-79 years. In the 18- to 64-year-old group, 25.5% reported moderate levels of HRSNs, and 18.3% reported severe HRSNs. In patients aged 65-79 years, 15.6% and 6.6% reported moderate HRSNs and severe HRSNs, respectively.
Severe HRSN was significantly associated with higher mortality risk in an adjusted analysis in patients aged 18-64 years (hazard ratio 2.00, P < .001).
Among adults aged 65-79 years, severe HRSN was not associated with higher mortality risk; however, in this older age group, those with 2-3 domains of medical financial hardship had significantly increased mortality risk compared with adults aged 65-79 years with zero domains of medical financial hardship (HR 1.58, P = .007).
Although the findings that HRSNs were associated with increased mortality risk, especially in the younger group, were not surprising, they serve as a call to action to address how HRSNs are contributing to cancer mortality, Mr. Biru said in an interview. “HRSNs, like food or housing insecurity, can lead to patients being unable to undergo the best treatment approach for their cancer,” he said.
What Are the Limitations and Research Gaps?
The study findings were limited by several factors including the use of self-reports to measure medical financial hardship, food insecurity, and nonmedical financial concerns in the NHIS, the researchers wrote in their discussion. More research with longer follow-up time beyond 1-5 years is needed, wrote Dr. Zheng and colleagues.
Studies also are needed to illustrate how patient navigation can help prevent patients from falling through the cracks with regard to social needs and financial hardships, Mr. Biru told this news organization.
Other areas for research include how addressing social needs affects health outcomes and whether programs designed to address social needs are effective, he said.
“Finally, qualitative research is needed to capture the lived experiences of cancer survivors facing these challenges. This knowledge can inform the development of more patient-centered interventions and policies that effectively address the social determinants of health and improve overall outcomes for all cancer survivors,” Mr. Biru said.
What Is the Takeaway Message for Clinicians?
HRSNs and financial hardship are significantly associated with increased risk of mortality in adult cancer survivors, Dr. Zheng and colleagues concluded. Looking ahead, comprehensive assessment of HRSNs and financial hardship may help clinicians connect patients with relevant services to mitigate the social and financial impacts of cancer, they wrote.
“The takeaway message for oncologists in practice is that addressing [HRSNs] and financial hardship is crucial for providing comprehensive and equitable cancer care,” Mr. Biru said during his interview.
“The impact of social determinants of health on cancer outcomes cannot be ignored, and oncologists play a vital role in identifying and addressing these needs,” he said. Sensitive, discussion-based screenings are needed to identify core needs such as food and transportation, but clinicians also can consider broader social factors and work with a team to connect patients to appropriate resources, he added.
“By recognizing the importance of HRSN screening and taking proactive steps to address these needs, oncologists can contribute to improving health outcomes, reducing healthcare disparities, and providing more equitable cancer care for their patients,” he said.
What Other Guidance Is Available?
“High-quality cancer care requires treating the whole person; measuring and addressing anything in their life that could result in poorer health outcomes is a key component of comprehensive care,” Mr. Biru emphasized.
In September 2023, the National Comprehensive Cancer Network (NCCN) convened a working group cochaired by Mr. Biru that developed recommendations for how oncology practices should routinely measure HRSNs (NCCN.org/social-needs).
“The working group proposed that every cancer patient be assessed for food, transportation access, and financial and housing security at least once a year, and be reassessed at every care transition point as well,” Mr. Biru said. Such screenings should include follow-up to connect patients with services to address any HRSNs they are experiencing, he added.
Lead author Dr. Zheng is employed by the American Cancer Society, which as a nonprofit receives funds from the public through fundraising and contributions, as well as some support from corporations and industry to support its mission programs and services. Mr. Biru had no financial conflicts to disclose.
Little is known about the specific association between health-related social needs (HRSNs) and mortality risk even though HRSNs, defined as challenges in affording food, housing, and other necessities of daily living, are potential challenges for cancer survivors, wrote Zhiyuan Zheng, PhD, of the American Cancer Society, Atlanta, and colleagues.
A 2020 study by Dr. Zheng and colleagues published in the Journal of the National Comprehensive Cancer Network (NCCN) showed that food insecurity and financial worries had a negative impact on cancer survivorship. In the new study, published in Cancer, the researchers identified cancer survivors using the 2013-2018 National Health Interview Survey (NHIS) and the NHIS Mortality File through December 31, 2019. The researchers examined mortality using the data from the Centers for Disease Control and Prevention’s National Death Index (NDI) through December 31, 2019, which links to the National Health Interview Survey Data used in the study.
Individuals’ HRSNs were categorized into three groups: severe, moderate, and minor/none. HRSNs included food insecurity and nonmedical financial concerns, such as housing costs (rent, mortgage). Medical financial hardship included material, psychological, and behavioral domains and was divided into three groups: 2-3 domains, 1 domain, or 0 domains.
What Are the Potential Financial Implications of this Research?
The high costs of cancer care often cause medical financial hardships for cancer survivors, and expenses also may cause psychological distress and nonmedical financial hardship as survivors try to make ends meet while facing medical bills, wrote Dr. Zheng and colleagues.
Policy makers are increasingly interested in adding HRSNs to insurance coverage; recent guidance from the Centers for Medicare & Medicaid Services (CMS) allows individual states to apply to provide nutrition and housing supports through state Medicaid programs, according to authors of a 2023 article published in JAMA Health Forum.
The new study adds to the understanding of how HRSNs impact people with cancer by examining the association with mortality risk, Yelak Biru, MSc, president and chief executive officer of the International Myeloma Foundation, said in an interview.
“This is a key area of study for addressing the disparities in treatments and outcomes that result in inequities,” said Mr. Biru, a patient advocate and multiple myeloma survivor who was not involved in the study.
What Does the New Study Show?
The new study characterized HRSNs in 5,855 adult cancer survivors aged 18-64 years and 5,918 aged 65-79 years. In the 18- to 64-year-old group, 25.5% reported moderate levels of HRSNs, and 18.3% reported severe HRSNs. In patients aged 65-79 years, 15.6% and 6.6% reported moderate HRSNs and severe HRSNs, respectively.
Severe HRSN was significantly associated with higher mortality risk in an adjusted analysis in patients aged 18-64 years (hazard ratio 2.00, P < .001).
Among adults aged 65-79 years, severe HRSN was not associated with higher mortality risk; however, in this older age group, those with 2-3 domains of medical financial hardship had significantly increased mortality risk compared with adults aged 65-79 years with zero domains of medical financial hardship (HR 1.58, P = .007).
Although the findings that HRSNs were associated with increased mortality risk, especially in the younger group, were not surprising, they serve as a call to action to address how HRSNs are contributing to cancer mortality, Mr. Biru said in an interview. “HRSNs, like food or housing insecurity, can lead to patients being unable to undergo the best treatment approach for their cancer,” he said.
What Are the Limitations and Research Gaps?
The study findings were limited by several factors including the use of self-reports to measure medical financial hardship, food insecurity, and nonmedical financial concerns in the NHIS, the researchers wrote in their discussion. More research with longer follow-up time beyond 1-5 years is needed, wrote Dr. Zheng and colleagues.
Studies also are needed to illustrate how patient navigation can help prevent patients from falling through the cracks with regard to social needs and financial hardships, Mr. Biru told this news organization.
Other areas for research include how addressing social needs affects health outcomes and whether programs designed to address social needs are effective, he said.
“Finally, qualitative research is needed to capture the lived experiences of cancer survivors facing these challenges. This knowledge can inform the development of more patient-centered interventions and policies that effectively address the social determinants of health and improve overall outcomes for all cancer survivors,” Mr. Biru said.
What Is the Takeaway Message for Clinicians?
HRSNs and financial hardship are significantly associated with increased risk of mortality in adult cancer survivors, Dr. Zheng and colleagues concluded. Looking ahead, comprehensive assessment of HRSNs and financial hardship may help clinicians connect patients with relevant services to mitigate the social and financial impacts of cancer, they wrote.
“The takeaway message for oncologists in practice is that addressing [HRSNs] and financial hardship is crucial for providing comprehensive and equitable cancer care,” Mr. Biru said during his interview.
“The impact of social determinants of health on cancer outcomes cannot be ignored, and oncologists play a vital role in identifying and addressing these needs,” he said. Sensitive, discussion-based screenings are needed to identify core needs such as food and transportation, but clinicians also can consider broader social factors and work with a team to connect patients to appropriate resources, he added.
“By recognizing the importance of HRSN screening and taking proactive steps to address these needs, oncologists can contribute to improving health outcomes, reducing healthcare disparities, and providing more equitable cancer care for their patients,” he said.
What Other Guidance Is Available?
“High-quality cancer care requires treating the whole person; measuring and addressing anything in their life that could result in poorer health outcomes is a key component of comprehensive care,” Mr. Biru emphasized.
In September 2023, the National Comprehensive Cancer Network (NCCN) convened a working group cochaired by Mr. Biru that developed recommendations for how oncology practices should routinely measure HRSNs (NCCN.org/social-needs).
“The working group proposed that every cancer patient be assessed for food, transportation access, and financial and housing security at least once a year, and be reassessed at every care transition point as well,” Mr. Biru said. Such screenings should include follow-up to connect patients with services to address any HRSNs they are experiencing, he added.
Lead author Dr. Zheng is employed by the American Cancer Society, which as a nonprofit receives funds from the public through fundraising and contributions, as well as some support from corporations and industry to support its mission programs and services. Mr. Biru had no financial conflicts to disclose.
FROM CANCER
Terminal Cancer: What Matters to Patients and Caregivers
New research found that patients and caregivers both tend to prioritize symptom control over life extension but often preferring a balance. Patients and caregivers, however, are less aligned on decisions about cost containment, with patients more likely to prioritize cost containment.
“Our research has revealed that patients and caregivers generally share similar end-of-life goals,” with a “notable exception” when it comes to costs, first author Semra Ozdemir, PhD, with the Lien Centre for Palliative Care, Duke-NUS Medical School, Singapore, told this news organization.
However, when patients and caregivers have a better understanding of the patient’s prognosis, both may be more inclined to avoid costly life-extending treatments and prioritize symptom management.
In other words, the survey suggests that “knowing the prognosis helps patients and their families set realistic expectations for care and adequately prepare for end-of-life decisions,” said Dr. Ozdemir.
This study was published online in JAMA Network Open.
Patients with advanced cancer often face difficult decisions: Do they opt for treatments that may — or may not — extend life or do they focus more on symptom control?
Family caregivers, who also play an important role in this decision-making process, may have different care goals. Some research suggests that caregivers tend to prioritize treatments that could extend life, whereas patients prioritize symptom management, but it’s less clear how these priorities may change over time and how patients and caregivers may influence each other.
In the current study, the researchers examined goals of care among patients with stage IV solid tumors and caregivers during the last 2 years of life, focusing on life extension vs symptom management and cost containment, as well as how these goals changed over time.
The survey included 210 patient-caregiver pairs, recruited from outpatient clinics at two major cancer centers in Singapore. Patients had a mean age of 63 years, and about half were men. The caregivers had a mean age of 49 years, and almost two third (63%) were women.
Overall, 34% patients and 29% caregivers prioritized symptom management over life extension, whereas 24% patients and 19% caregivers prioritized life extension. Most patients and caregivers preferred balancing the two, with 34%-47% patients and 37%-69% caregivers supporting this approach.
When balancing cost and treatment decisions, however, patients were more likely to prioritize containing costs — 28% vs 17% for caregivers — over extending life — 26% of patients vs 35% of caregivers.
Cost containment tended to be more of a priority for older patients, those with a higher symptom burden, and those with less family caregiver support. For caregivers, cost containment was more of a priority for those who reported that caregiving had a big impact on their finances, those with worse self-esteem related to their caregiving abilities, as well as those caring for older patients.
To better align cost containment priorities between patients and caregivers, it’s essential for families to engage in open and thorough discussions about the allocation of resources, Dr. Ozdemir said.
Although “patients, families, and physicians often avoid discussions about prognosis,” such conversations are essential for setting realistic expectations for care and adequately preparing for end-of-life decisions, Dr. Ozdemir told this news organization.
“These conversations should aim to balance competing interests and create care plans that are mutually acceptable to both patients and caregivers,” she said, adding that “this approach will help in minimizing any potential conflicts and ensure that both parties feel respected and understood in their decision-making process.”
Managing Unrealistic Expectations
As patients approached the end of life, neither patients nor caregivers shifted their priorities from life extension to symptom management.
This finding raises concerns because it suggests that many patients hold unrealistic expectations regarding their care and “underscores the need for continuous dialogue and reassessment of care goals throughout the progression of illness,” Dr. Ozdemir said.
“This stability in preferences over time suggests that initial care decisions are deeply ingrained or that there may be a lack of ongoing communication about evolving care needs and possibilities as conditions change,” Ozdemir said.
Yet, it can be hard to define what unrealistic expectations mean, said Olivia Seecof, MD, who wasn’t involved in the study.
“I think people are hopeful that a devastating diagnosis won’t lead to the end of their life and that there will be a treatment or something that will change [their prognosis], and they’ll get better,” said Dr. Seecof, palliative care expert with the Supportive Oncology Program at NYU Langone Health’s Perlmutter Cancer Center in New York City.
Giving patients and caregivers a realistic understanding of the prognosis is important, but “there’s more to it than just telling the patient their diagnosis,” she said.
“We have to plan for end of life, what it can look like,” said Dr. Seecof, adding that “often we don’t do a very good job of talking about that early on in an illness course.”
Overall, though, Dr. Seecof stressed that no two patients or situations are the same, and it’s important to understand what’s important in each scenario. End-of-life care requires “an individual approach because every patient is different, even if they have the same diagnosis as someone else,” she said.
This work was supported by funding from the Singapore Millennium Foundation and the Lien Centre for Palliative Care. Dr. Ozdemir and Dr. Seecof had no relevant disclosures.
A version of this article appeared on Medscape.com.
New research found that patients and caregivers both tend to prioritize symptom control over life extension but often preferring a balance. Patients and caregivers, however, are less aligned on decisions about cost containment, with patients more likely to prioritize cost containment.
“Our research has revealed that patients and caregivers generally share similar end-of-life goals,” with a “notable exception” when it comes to costs, first author Semra Ozdemir, PhD, with the Lien Centre for Palliative Care, Duke-NUS Medical School, Singapore, told this news organization.
However, when patients and caregivers have a better understanding of the patient’s prognosis, both may be more inclined to avoid costly life-extending treatments and prioritize symptom management.
In other words, the survey suggests that “knowing the prognosis helps patients and their families set realistic expectations for care and adequately prepare for end-of-life decisions,” said Dr. Ozdemir.
This study was published online in JAMA Network Open.
Patients with advanced cancer often face difficult decisions: Do they opt for treatments that may — or may not — extend life or do they focus more on symptom control?
Family caregivers, who also play an important role in this decision-making process, may have different care goals. Some research suggests that caregivers tend to prioritize treatments that could extend life, whereas patients prioritize symptom management, but it’s less clear how these priorities may change over time and how patients and caregivers may influence each other.
In the current study, the researchers examined goals of care among patients with stage IV solid tumors and caregivers during the last 2 years of life, focusing on life extension vs symptom management and cost containment, as well as how these goals changed over time.
The survey included 210 patient-caregiver pairs, recruited from outpatient clinics at two major cancer centers in Singapore. Patients had a mean age of 63 years, and about half were men. The caregivers had a mean age of 49 years, and almost two third (63%) were women.
Overall, 34% patients and 29% caregivers prioritized symptom management over life extension, whereas 24% patients and 19% caregivers prioritized life extension. Most patients and caregivers preferred balancing the two, with 34%-47% patients and 37%-69% caregivers supporting this approach.
When balancing cost and treatment decisions, however, patients were more likely to prioritize containing costs — 28% vs 17% for caregivers — over extending life — 26% of patients vs 35% of caregivers.
Cost containment tended to be more of a priority for older patients, those with a higher symptom burden, and those with less family caregiver support. For caregivers, cost containment was more of a priority for those who reported that caregiving had a big impact on their finances, those with worse self-esteem related to their caregiving abilities, as well as those caring for older patients.
To better align cost containment priorities between patients and caregivers, it’s essential for families to engage in open and thorough discussions about the allocation of resources, Dr. Ozdemir said.
Although “patients, families, and physicians often avoid discussions about prognosis,” such conversations are essential for setting realistic expectations for care and adequately preparing for end-of-life decisions, Dr. Ozdemir told this news organization.
“These conversations should aim to balance competing interests and create care plans that are mutually acceptable to both patients and caregivers,” she said, adding that “this approach will help in minimizing any potential conflicts and ensure that both parties feel respected and understood in their decision-making process.”
Managing Unrealistic Expectations
As patients approached the end of life, neither patients nor caregivers shifted their priorities from life extension to symptom management.
This finding raises concerns because it suggests that many patients hold unrealistic expectations regarding their care and “underscores the need for continuous dialogue and reassessment of care goals throughout the progression of illness,” Dr. Ozdemir said.
“This stability in preferences over time suggests that initial care decisions are deeply ingrained or that there may be a lack of ongoing communication about evolving care needs and possibilities as conditions change,” Ozdemir said.
Yet, it can be hard to define what unrealistic expectations mean, said Olivia Seecof, MD, who wasn’t involved in the study.
“I think people are hopeful that a devastating diagnosis won’t lead to the end of their life and that there will be a treatment or something that will change [their prognosis], and they’ll get better,” said Dr. Seecof, palliative care expert with the Supportive Oncology Program at NYU Langone Health’s Perlmutter Cancer Center in New York City.
Giving patients and caregivers a realistic understanding of the prognosis is important, but “there’s more to it than just telling the patient their diagnosis,” she said.
“We have to plan for end of life, what it can look like,” said Dr. Seecof, adding that “often we don’t do a very good job of talking about that early on in an illness course.”
Overall, though, Dr. Seecof stressed that no two patients or situations are the same, and it’s important to understand what’s important in each scenario. End-of-life care requires “an individual approach because every patient is different, even if they have the same diagnosis as someone else,” she said.
This work was supported by funding from the Singapore Millennium Foundation and the Lien Centre for Palliative Care. Dr. Ozdemir and Dr. Seecof had no relevant disclosures.
A version of this article appeared on Medscape.com.
New research found that patients and caregivers both tend to prioritize symptom control over life extension but often preferring a balance. Patients and caregivers, however, are less aligned on decisions about cost containment, with patients more likely to prioritize cost containment.
“Our research has revealed that patients and caregivers generally share similar end-of-life goals,” with a “notable exception” when it comes to costs, first author Semra Ozdemir, PhD, with the Lien Centre for Palliative Care, Duke-NUS Medical School, Singapore, told this news organization.
However, when patients and caregivers have a better understanding of the patient’s prognosis, both may be more inclined to avoid costly life-extending treatments and prioritize symptom management.
In other words, the survey suggests that “knowing the prognosis helps patients and their families set realistic expectations for care and adequately prepare for end-of-life decisions,” said Dr. Ozdemir.
This study was published online in JAMA Network Open.
Patients with advanced cancer often face difficult decisions: Do they opt for treatments that may — or may not — extend life or do they focus more on symptom control?
Family caregivers, who also play an important role in this decision-making process, may have different care goals. Some research suggests that caregivers tend to prioritize treatments that could extend life, whereas patients prioritize symptom management, but it’s less clear how these priorities may change over time and how patients and caregivers may influence each other.
In the current study, the researchers examined goals of care among patients with stage IV solid tumors and caregivers during the last 2 years of life, focusing on life extension vs symptom management and cost containment, as well as how these goals changed over time.
The survey included 210 patient-caregiver pairs, recruited from outpatient clinics at two major cancer centers in Singapore. Patients had a mean age of 63 years, and about half were men. The caregivers had a mean age of 49 years, and almost two third (63%) were women.
Overall, 34% patients and 29% caregivers prioritized symptom management over life extension, whereas 24% patients and 19% caregivers prioritized life extension. Most patients and caregivers preferred balancing the two, with 34%-47% patients and 37%-69% caregivers supporting this approach.
When balancing cost and treatment decisions, however, patients were more likely to prioritize containing costs — 28% vs 17% for caregivers — over extending life — 26% of patients vs 35% of caregivers.
Cost containment tended to be more of a priority for older patients, those with a higher symptom burden, and those with less family caregiver support. For caregivers, cost containment was more of a priority for those who reported that caregiving had a big impact on their finances, those with worse self-esteem related to their caregiving abilities, as well as those caring for older patients.
To better align cost containment priorities between patients and caregivers, it’s essential for families to engage in open and thorough discussions about the allocation of resources, Dr. Ozdemir said.
Although “patients, families, and physicians often avoid discussions about prognosis,” such conversations are essential for setting realistic expectations for care and adequately preparing for end-of-life decisions, Dr. Ozdemir told this news organization.
“These conversations should aim to balance competing interests and create care plans that are mutually acceptable to both patients and caregivers,” she said, adding that “this approach will help in minimizing any potential conflicts and ensure that both parties feel respected and understood in their decision-making process.”
Managing Unrealistic Expectations
As patients approached the end of life, neither patients nor caregivers shifted their priorities from life extension to symptom management.
This finding raises concerns because it suggests that many patients hold unrealistic expectations regarding their care and “underscores the need for continuous dialogue and reassessment of care goals throughout the progression of illness,” Dr. Ozdemir said.
“This stability in preferences over time suggests that initial care decisions are deeply ingrained or that there may be a lack of ongoing communication about evolving care needs and possibilities as conditions change,” Ozdemir said.
Yet, it can be hard to define what unrealistic expectations mean, said Olivia Seecof, MD, who wasn’t involved in the study.
“I think people are hopeful that a devastating diagnosis won’t lead to the end of their life and that there will be a treatment or something that will change [their prognosis], and they’ll get better,” said Dr. Seecof, palliative care expert with the Supportive Oncology Program at NYU Langone Health’s Perlmutter Cancer Center in New York City.
Giving patients and caregivers a realistic understanding of the prognosis is important, but “there’s more to it than just telling the patient their diagnosis,” she said.
“We have to plan for end of life, what it can look like,” said Dr. Seecof, adding that “often we don’t do a very good job of talking about that early on in an illness course.”
Overall, though, Dr. Seecof stressed that no two patients or situations are the same, and it’s important to understand what’s important in each scenario. End-of-life care requires “an individual approach because every patient is different, even if they have the same diagnosis as someone else,” she said.
This work was supported by funding from the Singapore Millennium Foundation and the Lien Centre for Palliative Care. Dr. Ozdemir and Dr. Seecof had no relevant disclosures.
A version of this article appeared on Medscape.com.
The Long, Controversial Search for a ‘Cancer Microbiome’
Last year, the controversy heightened when experts questioned a high-profile study — a 2020 analysis claiming that the tumors of 33 different cancers had their own unique microbiomes — on whether the “signature” of these bacterial compositions could help diagnose cancer.
The incident renewed the spotlight on “tumor microbiomes” because of the bold claims of the original paper and the strongly worded refutations of those claims. The broader field has focused primarily on ways the body’s microbiome interacts with cancers and cancer treatment.
This controversy has highlighted the challenges of making headway in a field where researchers may not even have the tools yet to puzzle-out the wide-ranging implications the microbiome holds for cancer diagnosis and treatment.
But it is also part of a provocative question within that larger field: whether tumors in the body, far from the natural microbiome in the gut, have their own thriving communities of bacteria, viruses, and fungi. And, if they do, how do those tumor microbiomes affect the development and progression of the cancer and the effectiveness of cancer therapies?
Cancer Controversy
The evidence is undeniable that some microbes can directly cause certain cancers and that the human gut microbiome can influence the effectiveness of certain therapies. Beyond that established science, however, the research has raised as many questions as answers about what we do and don’t know about microbiota and cancer.
The only confirmed microbiomes are on the skin and in the gut, mouth, and vagina, which are all areas with an easy direct route for bacteria to enter and grow in or on the body. A series of papers in recent years have suggested that other internal organs, and tumors within them, may have their own microbiomes.
“Whether microbes exist in tumors of internal organs beyond body surfaces exposed to the environment is a different matter,” said Ivan Vujkovic-Cvijin, PhD, an assistant professor of biomedical sciences and gastroenterology at Cedars-Sinai Medical Center in Los Angeles, whose lab studies how human gut microbes affect inflammatory diseases. “We’ve only recently had the tools to study that question on a molecular level, and the reported results have been conflicting.”
For example, research allegedly identified microbiota in the human placenta nearly one decade ago. But subsequent research contradicted those claims and showed that the source of the “placental microbiome” was actually contamination. Subsequent similar studies for other parts of the body faced the same scrutiny and, often, eventual debunking.
“Most likely, our immune system has undergone selective pressure to eliminate everything that crosses the gut barrier because there’s not much benefit to the body to have bacteria run amok in our internal organs,” Dr. Vujkovic-Cvijin said. “That can only disrupt the functioning of our tissues, to have an external organism living inside them.”
The controversy that erupted last summer, surrounding research from the lab of Rob Knight, PhD, at the University of California, San Diego, centered on a slightly different but related question: Could tumors harbor their own microbiomes?
This news organization spoke with two of the authors who published a paper contesting Dr. Knight’s findings: Steven Salzberg, PhD, a professor of biomedical engineering at John Hopkins Medicine, Baltimore, Maryland, and Abraham Gihawi, PhD, a research fellow at Norwich Medical School at the University of East Anglia in the United Kingdom.
Dr. Salzberg described two major problems with Dr. Knight’s study.
“What they found were false positives because of contamination in the database and flaws in their methods,” Dr. Salzberg said. “I can’t prove there’s no cancer microbiome, but I can say the cancer microbiomes that they reported don’t exist because the species they were finding aren’t there.”
Dr. Knight disagrees with Dr. Salzberg’s findings, noting that Dr. Salzberg and his co-authors did not examine the publicly available databases used in his study. In a written response, he said that his team’s examination of the database revealed that less than 1% of the microbial genomes overlapped with human ones and that removing them did not change their findings.
Dr. Knight also noted that his team could still “distinguish cancer types by their microbiome” even after running their analysis without the technique that Dr. Salzberg found fault with.
Dr. Salzberg said that the database linked above is not the one Dr. Knight’s study used, however. “The primary database in their study was never made public (it’s too large, they said), and it has/had about 69,000 genomes,” Dr. Salzberg said by email. “But even if we did, this is irrelevant. He’s trying to distract from the primary errors in their study,” which Dr. Salzberg said Dr. Knight’s team has not addressed.
The critiques Dr. Salzberg raised have been leveled at other studies investigating microbiomes specifically within tumors and independent of the body’s microbiome.
For example, a 2019 study in Nature described a fungal microbiome in pancreatic cancer that a Nature paper 4 years later directly contradicted, citing flaws that invalidated the original findings. A different 2019 study in Cell examined pancreatic tumor microbiota and patient outcomes, but it’s unclear whether the microorganisms moved from the gut to the pancreas or “constitute a durably colonized community that lives inside the tumor,” which remains a matter of debate, Dr. Vujkovic-Cvijin said.
A 2020 study in Science suggested diverse microbial communities in seven tumor types, but those findings were similarly called into question. That study stated that “bacteria were first detected in human tumors more than 100 years ago” and that “bacteria are well-known residents in human tumors,” but Dr. Salzberg considers those statements misleading.
It’s true that bacteria and viruses have been detected in tumors because “there’s very good evidence that an acute infection caused by a very small number of viruses and bacteria can cause a tumor,” Dr. Salzberg said. Human papillomavirus, for example, can cause six different types of cancer. Inflammation and ulcers caused by Helicobacter pylori may progress to stomach cancer, and Fusobacterium nucleatum and Enterococcus faecalis have been shown to contribute to colorectal cancer. Those examples differ from a microbiome; this “a community of bacteria and possibly other microscopic bugs, like fungi, that are happily living in the tumor” the same way microbes reside in our guts, he said.
Dr. Knight said that many bacteria his team identified “have been confirmed independently in subsequent work.” He acknowledged, however, that more research is needed.
Several of the contested studies above were among a lengthy list that Dr. Knight provided, noting that most of the disagreements “have two sides to them, and critiques from one particular group does not immediately invalidate a reported finding.”
Yet, many of the papers Dr. Knight listed are precisely the types that skeptics like Dr. Salzberg believe are too flawed to draw reliable conclusions.
“I think many agree that microbes may exist within tumors that are exposed to the environment, like tumors of the skin, gut, and mouth,” Dr. Vujkovic-Cvijin said. It’s less clear, however, whether tumors further from the body’s microbiome harbor any microbes or where they came from if they do. Microbial signals in organs elsewhere in the body become faint quickly, he said.
Underdeveloped Technology
Though Dr. Salzberg said that the concept of a tumor microbiome is “implausible” because there’s no easy route for bacteria to reach internal organs, it’s unclear whether scientists have the technology yet to adequately answer this question.
For one thing, samples in these types of studies are typically “ultra-low biomass samples, where the signal — the amount of microbes in the sample — is so low that it’s comparable to how much would be expected to be found in reagents and environmental contamination through processing,” Dr. Vujkovic-Cvijin explained. Many polymerases used to amplify a DNA signal, for example, are made in bacteria and may retain trace amounts identified in these studies.
Dr. Knight agreed that low biomass is a challenge in this field but is not an unsurmountable one.
Another challenge is that study samples, as with Dr. Knight’s work, were collected during routine surgeries without the intent to find a microbial signal. Simply using a scalpel to cut through the skin means cutting through a layer of bacteria, and surgery rooms are not designed to eliminate all bacteria. Some work has even shown there is a “hospital microbiome,” so “you can easily have that creep into your signal and mistake it for tumor-resident bacteria,” Dr. Vujkovic-Cvijin said.
Dr. Knight asserted that the samples are taken under sterile conditions, but other researchers do not think the level of sterility necessary for completely clean samples is possible.
“Just because it’s in your sample doesn’t mean it was in your tumor,” Dr. Gihawi said.
Even if scientists can retrieve a reliable sample without contamination, analyzing it requires comparing the genetic material to existing databases of microbial genomes. Yet, contamination and misclassification of genetic sequences can be problems in those reference genomes too, Dr. Gihawi explained.
Machine learning algorithms have a role in interpreting data, but “we need to be careful of what we use them for,” he added.
“These techniques are in their infancy, and we’re starting to chase them down, which is why we need to move microbiome research in a way that can be used clinically,” Dr. Gihawi said.
Influence on Cancer Treatment Outcomes
Again, however, the question of whether microbiomes exist within tumors is only one slice of the much larger field looking at microbiomes and cancer, including its influence on cancer treatment outcomes. Although much remains to be learned, less controversy exists over the thousands of studies in the past two decades that have gradually revealed how the body’s microbiome can affect both the course of a cancer and the effectiveness of different treatments.
The growing research showing the importance of the gut microbiome in cancer treatments is not surprising given its role in immunity more broadly. Because the human immune system must recognize and defend against microbes, the microbiome helps train it, Dr. Vujkovic-Cvijin said.
Some bacteria can escape the gut — a phenomenon called bacterial translocation — and may aid in fighting tumors. To grow large enough to be seen on imaging, tumors need to evolve several abilities, such as growing enough vascularization to receive blood flow and shutting down local immune responses.
“Any added boost, like immunotherapy, has a chance of breaking through that immune forcefield and killing the tumor cells,” Dr. Vujkovic-Cvijin said. Escaped gut bacteria may provide that boost.
“There’s a lot of evidence that depletion of the gut microbiome impairs immunotherapy and chemotherapy. The thinking behind some of those studies is that gut microbes can cross the gut barrier and when they do, they activate the immune system,” he said.
In mice engineered to have sterile guts, for example, the lack of bacteria results in less effective immune systems, Dr. Vujkovic-Cvijin pointed out. A host of research has shown that antibiotic exposure during and even 6 months before immunotherapy dramatically reduces survival rates. “That’s pretty convincing to me that gut microbes are important,” he said.
Dr. Vujkovic-Cvijin cautioned that there continues to be controversy on understanding which bacteria are important for response to immunotherapy. “The field is still in its infancy in terms of understanding which bacteria are most important for these effects,” he said.
Dr. Knight suggested that escaped bacteria may be the genesis of the ones that he and other researchers believe exist in tumors. “Because tumor microbes must come from somewhere, it is to be expected that some of those microbes will be co-opted from body-site specific commensals.”
It’s also possible that metabolites released from gut bacteria escape the gut and could theoretically affect distant tumor growth, Dr. Gihawi said. The most promising avenue of research in this area is metabolites being used as biomarkers, added Dr. Gihawi, whose lab published research on a link between bacteria detected in men’s urine and a more aggressive subset of prostate cancers. But that research is not far enough along to develop lab tests for clinical use, he noted.
No Consensus Yet
Even before the controversy erupted around Dr. Knight’s research, he co-founded the company Micronoma to develop cancer tests based on his microbe findings. The company has raised $17.5 million from private investors as of August 2023 and received the US Food and Drug Administration’s Breakthrough Device designation, allowing the firm to fast-track clinical trials testing the technology. The recent critiques have not changed the company’s plans.
It’s safe to say that scientists will continue to research and debate the possibility of tumor microbiomes until a consensus emerges.
“The field is evolving and studies testing the reproducibility of tumor-resident microbial signals are essential for developing our understanding in this area,” Dr. Vujkovic-Cvijin said.
Even if that path ultimately leads nowhere, as Dr. Salzberg expects, research into microbiomes and cancer has plenty of other directions to go.
“I’m actually quite an optimist,” Dr. Gihawi said. “I think there’s a lot of scope for some really good research here, especially in the sites where we know there is a strong microbiome, such as the gastrointestinal tract.”
A version of this article appeared on Medscape.com.
Last year, the controversy heightened when experts questioned a high-profile study — a 2020 analysis claiming that the tumors of 33 different cancers had their own unique microbiomes — on whether the “signature” of these bacterial compositions could help diagnose cancer.
The incident renewed the spotlight on “tumor microbiomes” because of the bold claims of the original paper and the strongly worded refutations of those claims. The broader field has focused primarily on ways the body’s microbiome interacts with cancers and cancer treatment.
This controversy has highlighted the challenges of making headway in a field where researchers may not even have the tools yet to puzzle-out the wide-ranging implications the microbiome holds for cancer diagnosis and treatment.
But it is also part of a provocative question within that larger field: whether tumors in the body, far from the natural microbiome in the gut, have their own thriving communities of bacteria, viruses, and fungi. And, if they do, how do those tumor microbiomes affect the development and progression of the cancer and the effectiveness of cancer therapies?
Cancer Controversy
The evidence is undeniable that some microbes can directly cause certain cancers and that the human gut microbiome can influence the effectiveness of certain therapies. Beyond that established science, however, the research has raised as many questions as answers about what we do and don’t know about microbiota and cancer.
The only confirmed microbiomes are on the skin and in the gut, mouth, and vagina, which are all areas with an easy direct route for bacteria to enter and grow in or on the body. A series of papers in recent years have suggested that other internal organs, and tumors within them, may have their own microbiomes.
“Whether microbes exist in tumors of internal organs beyond body surfaces exposed to the environment is a different matter,” said Ivan Vujkovic-Cvijin, PhD, an assistant professor of biomedical sciences and gastroenterology at Cedars-Sinai Medical Center in Los Angeles, whose lab studies how human gut microbes affect inflammatory diseases. “We’ve only recently had the tools to study that question on a molecular level, and the reported results have been conflicting.”
For example, research allegedly identified microbiota in the human placenta nearly one decade ago. But subsequent research contradicted those claims and showed that the source of the “placental microbiome” was actually contamination. Subsequent similar studies for other parts of the body faced the same scrutiny and, often, eventual debunking.
“Most likely, our immune system has undergone selective pressure to eliminate everything that crosses the gut barrier because there’s not much benefit to the body to have bacteria run amok in our internal organs,” Dr. Vujkovic-Cvijin said. “That can only disrupt the functioning of our tissues, to have an external organism living inside them.”
The controversy that erupted last summer, surrounding research from the lab of Rob Knight, PhD, at the University of California, San Diego, centered on a slightly different but related question: Could tumors harbor their own microbiomes?
This news organization spoke with two of the authors who published a paper contesting Dr. Knight’s findings: Steven Salzberg, PhD, a professor of biomedical engineering at John Hopkins Medicine, Baltimore, Maryland, and Abraham Gihawi, PhD, a research fellow at Norwich Medical School at the University of East Anglia in the United Kingdom.
Dr. Salzberg described two major problems with Dr. Knight’s study.
“What they found were false positives because of contamination in the database and flaws in their methods,” Dr. Salzberg said. “I can’t prove there’s no cancer microbiome, but I can say the cancer microbiomes that they reported don’t exist because the species they were finding aren’t there.”
Dr. Knight disagrees with Dr. Salzberg’s findings, noting that Dr. Salzberg and his co-authors did not examine the publicly available databases used in his study. In a written response, he said that his team’s examination of the database revealed that less than 1% of the microbial genomes overlapped with human ones and that removing them did not change their findings.
Dr. Knight also noted that his team could still “distinguish cancer types by their microbiome” even after running their analysis without the technique that Dr. Salzberg found fault with.
Dr. Salzberg said that the database linked above is not the one Dr. Knight’s study used, however. “The primary database in their study was never made public (it’s too large, they said), and it has/had about 69,000 genomes,” Dr. Salzberg said by email. “But even if we did, this is irrelevant. He’s trying to distract from the primary errors in their study,” which Dr. Salzberg said Dr. Knight’s team has not addressed.
The critiques Dr. Salzberg raised have been leveled at other studies investigating microbiomes specifically within tumors and independent of the body’s microbiome.
For example, a 2019 study in Nature described a fungal microbiome in pancreatic cancer that a Nature paper 4 years later directly contradicted, citing flaws that invalidated the original findings. A different 2019 study in Cell examined pancreatic tumor microbiota and patient outcomes, but it’s unclear whether the microorganisms moved from the gut to the pancreas or “constitute a durably colonized community that lives inside the tumor,” which remains a matter of debate, Dr. Vujkovic-Cvijin said.
A 2020 study in Science suggested diverse microbial communities in seven tumor types, but those findings were similarly called into question. That study stated that “bacteria were first detected in human tumors more than 100 years ago” and that “bacteria are well-known residents in human tumors,” but Dr. Salzberg considers those statements misleading.
It’s true that bacteria and viruses have been detected in tumors because “there’s very good evidence that an acute infection caused by a very small number of viruses and bacteria can cause a tumor,” Dr. Salzberg said. Human papillomavirus, for example, can cause six different types of cancer. Inflammation and ulcers caused by Helicobacter pylori may progress to stomach cancer, and Fusobacterium nucleatum and Enterococcus faecalis have been shown to contribute to colorectal cancer. Those examples differ from a microbiome; this “a community of bacteria and possibly other microscopic bugs, like fungi, that are happily living in the tumor” the same way microbes reside in our guts, he said.
Dr. Knight said that many bacteria his team identified “have been confirmed independently in subsequent work.” He acknowledged, however, that more research is needed.
Several of the contested studies above were among a lengthy list that Dr. Knight provided, noting that most of the disagreements “have two sides to them, and critiques from one particular group does not immediately invalidate a reported finding.”
Yet, many of the papers Dr. Knight listed are precisely the types that skeptics like Dr. Salzberg believe are too flawed to draw reliable conclusions.
“I think many agree that microbes may exist within tumors that are exposed to the environment, like tumors of the skin, gut, and mouth,” Dr. Vujkovic-Cvijin said. It’s less clear, however, whether tumors further from the body’s microbiome harbor any microbes or where they came from if they do. Microbial signals in organs elsewhere in the body become faint quickly, he said.
Underdeveloped Technology
Though Dr. Salzberg said that the concept of a tumor microbiome is “implausible” because there’s no easy route for bacteria to reach internal organs, it’s unclear whether scientists have the technology yet to adequately answer this question.
For one thing, samples in these types of studies are typically “ultra-low biomass samples, where the signal — the amount of microbes in the sample — is so low that it’s comparable to how much would be expected to be found in reagents and environmental contamination through processing,” Dr. Vujkovic-Cvijin explained. Many polymerases used to amplify a DNA signal, for example, are made in bacteria and may retain trace amounts identified in these studies.
Dr. Knight agreed that low biomass is a challenge in this field but is not an unsurmountable one.
Another challenge is that study samples, as with Dr. Knight’s work, were collected during routine surgeries without the intent to find a microbial signal. Simply using a scalpel to cut through the skin means cutting through a layer of bacteria, and surgery rooms are not designed to eliminate all bacteria. Some work has even shown there is a “hospital microbiome,” so “you can easily have that creep into your signal and mistake it for tumor-resident bacteria,” Dr. Vujkovic-Cvijin said.
Dr. Knight asserted that the samples are taken under sterile conditions, but other researchers do not think the level of sterility necessary for completely clean samples is possible.
“Just because it’s in your sample doesn’t mean it was in your tumor,” Dr. Gihawi said.
Even if scientists can retrieve a reliable sample without contamination, analyzing it requires comparing the genetic material to existing databases of microbial genomes. Yet, contamination and misclassification of genetic sequences can be problems in those reference genomes too, Dr. Gihawi explained.
Machine learning algorithms have a role in interpreting data, but “we need to be careful of what we use them for,” he added.
“These techniques are in their infancy, and we’re starting to chase them down, which is why we need to move microbiome research in a way that can be used clinically,” Dr. Gihawi said.
Influence on Cancer Treatment Outcomes
Again, however, the question of whether microbiomes exist within tumors is only one slice of the much larger field looking at microbiomes and cancer, including its influence on cancer treatment outcomes. Although much remains to be learned, less controversy exists over the thousands of studies in the past two decades that have gradually revealed how the body’s microbiome can affect both the course of a cancer and the effectiveness of different treatments.
The growing research showing the importance of the gut microbiome in cancer treatments is not surprising given its role in immunity more broadly. Because the human immune system must recognize and defend against microbes, the microbiome helps train it, Dr. Vujkovic-Cvijin said.
Some bacteria can escape the gut — a phenomenon called bacterial translocation — and may aid in fighting tumors. To grow large enough to be seen on imaging, tumors need to evolve several abilities, such as growing enough vascularization to receive blood flow and shutting down local immune responses.
“Any added boost, like immunotherapy, has a chance of breaking through that immune forcefield and killing the tumor cells,” Dr. Vujkovic-Cvijin said. Escaped gut bacteria may provide that boost.
“There’s a lot of evidence that depletion of the gut microbiome impairs immunotherapy and chemotherapy. The thinking behind some of those studies is that gut microbes can cross the gut barrier and when they do, they activate the immune system,” he said.
In mice engineered to have sterile guts, for example, the lack of bacteria results in less effective immune systems, Dr. Vujkovic-Cvijin pointed out. A host of research has shown that antibiotic exposure during and even 6 months before immunotherapy dramatically reduces survival rates. “That’s pretty convincing to me that gut microbes are important,” he said.
Dr. Vujkovic-Cvijin cautioned that there continues to be controversy on understanding which bacteria are important for response to immunotherapy. “The field is still in its infancy in terms of understanding which bacteria are most important for these effects,” he said.
Dr. Knight suggested that escaped bacteria may be the genesis of the ones that he and other researchers believe exist in tumors. “Because tumor microbes must come from somewhere, it is to be expected that some of those microbes will be co-opted from body-site specific commensals.”
It’s also possible that metabolites released from gut bacteria escape the gut and could theoretically affect distant tumor growth, Dr. Gihawi said. The most promising avenue of research in this area is metabolites being used as biomarkers, added Dr. Gihawi, whose lab published research on a link between bacteria detected in men’s urine and a more aggressive subset of prostate cancers. But that research is not far enough along to develop lab tests for clinical use, he noted.
No Consensus Yet
Even before the controversy erupted around Dr. Knight’s research, he co-founded the company Micronoma to develop cancer tests based on his microbe findings. The company has raised $17.5 million from private investors as of August 2023 and received the US Food and Drug Administration’s Breakthrough Device designation, allowing the firm to fast-track clinical trials testing the technology. The recent critiques have not changed the company’s plans.
It’s safe to say that scientists will continue to research and debate the possibility of tumor microbiomes until a consensus emerges.
“The field is evolving and studies testing the reproducibility of tumor-resident microbial signals are essential for developing our understanding in this area,” Dr. Vujkovic-Cvijin said.
Even if that path ultimately leads nowhere, as Dr. Salzberg expects, research into microbiomes and cancer has plenty of other directions to go.
“I’m actually quite an optimist,” Dr. Gihawi said. “I think there’s a lot of scope for some really good research here, especially in the sites where we know there is a strong microbiome, such as the gastrointestinal tract.”
A version of this article appeared on Medscape.com.
Last year, the controversy heightened when experts questioned a high-profile study — a 2020 analysis claiming that the tumors of 33 different cancers had their own unique microbiomes — on whether the “signature” of these bacterial compositions could help diagnose cancer.
The incident renewed the spotlight on “tumor microbiomes” because of the bold claims of the original paper and the strongly worded refutations of those claims. The broader field has focused primarily on ways the body’s microbiome interacts with cancers and cancer treatment.
This controversy has highlighted the challenges of making headway in a field where researchers may not even have the tools yet to puzzle-out the wide-ranging implications the microbiome holds for cancer diagnosis and treatment.
But it is also part of a provocative question within that larger field: whether tumors in the body, far from the natural microbiome in the gut, have their own thriving communities of bacteria, viruses, and fungi. And, if they do, how do those tumor microbiomes affect the development and progression of the cancer and the effectiveness of cancer therapies?
Cancer Controversy
The evidence is undeniable that some microbes can directly cause certain cancers and that the human gut microbiome can influence the effectiveness of certain therapies. Beyond that established science, however, the research has raised as many questions as answers about what we do and don’t know about microbiota and cancer.
The only confirmed microbiomes are on the skin and in the gut, mouth, and vagina, which are all areas with an easy direct route for bacteria to enter and grow in or on the body. A series of papers in recent years have suggested that other internal organs, and tumors within them, may have their own microbiomes.
“Whether microbes exist in tumors of internal organs beyond body surfaces exposed to the environment is a different matter,” said Ivan Vujkovic-Cvijin, PhD, an assistant professor of biomedical sciences and gastroenterology at Cedars-Sinai Medical Center in Los Angeles, whose lab studies how human gut microbes affect inflammatory diseases. “We’ve only recently had the tools to study that question on a molecular level, and the reported results have been conflicting.”
For example, research allegedly identified microbiota in the human placenta nearly one decade ago. But subsequent research contradicted those claims and showed that the source of the “placental microbiome” was actually contamination. Subsequent similar studies for other parts of the body faced the same scrutiny and, often, eventual debunking.
“Most likely, our immune system has undergone selective pressure to eliminate everything that crosses the gut barrier because there’s not much benefit to the body to have bacteria run amok in our internal organs,” Dr. Vujkovic-Cvijin said. “That can only disrupt the functioning of our tissues, to have an external organism living inside them.”
The controversy that erupted last summer, surrounding research from the lab of Rob Knight, PhD, at the University of California, San Diego, centered on a slightly different but related question: Could tumors harbor their own microbiomes?
This news organization spoke with two of the authors who published a paper contesting Dr. Knight’s findings: Steven Salzberg, PhD, a professor of biomedical engineering at John Hopkins Medicine, Baltimore, Maryland, and Abraham Gihawi, PhD, a research fellow at Norwich Medical School at the University of East Anglia in the United Kingdom.
Dr. Salzberg described two major problems with Dr. Knight’s study.
“What they found were false positives because of contamination in the database and flaws in their methods,” Dr. Salzberg said. “I can’t prove there’s no cancer microbiome, but I can say the cancer microbiomes that they reported don’t exist because the species they were finding aren’t there.”
Dr. Knight disagrees with Dr. Salzberg’s findings, noting that Dr. Salzberg and his co-authors did not examine the publicly available databases used in his study. In a written response, he said that his team’s examination of the database revealed that less than 1% of the microbial genomes overlapped with human ones and that removing them did not change their findings.
Dr. Knight also noted that his team could still “distinguish cancer types by their microbiome” even after running their analysis without the technique that Dr. Salzberg found fault with.
Dr. Salzberg said that the database linked above is not the one Dr. Knight’s study used, however. “The primary database in their study was never made public (it’s too large, they said), and it has/had about 69,000 genomes,” Dr. Salzberg said by email. “But even if we did, this is irrelevant. He’s trying to distract from the primary errors in their study,” which Dr. Salzberg said Dr. Knight’s team has not addressed.
The critiques Dr. Salzberg raised have been leveled at other studies investigating microbiomes specifically within tumors and independent of the body’s microbiome.
For example, a 2019 study in Nature described a fungal microbiome in pancreatic cancer that a Nature paper 4 years later directly contradicted, citing flaws that invalidated the original findings. A different 2019 study in Cell examined pancreatic tumor microbiota and patient outcomes, but it’s unclear whether the microorganisms moved from the gut to the pancreas or “constitute a durably colonized community that lives inside the tumor,” which remains a matter of debate, Dr. Vujkovic-Cvijin said.
A 2020 study in Science suggested diverse microbial communities in seven tumor types, but those findings were similarly called into question. That study stated that “bacteria were first detected in human tumors more than 100 years ago” and that “bacteria are well-known residents in human tumors,” but Dr. Salzberg considers those statements misleading.
It’s true that bacteria and viruses have been detected in tumors because “there’s very good evidence that an acute infection caused by a very small number of viruses and bacteria can cause a tumor,” Dr. Salzberg said. Human papillomavirus, for example, can cause six different types of cancer. Inflammation and ulcers caused by Helicobacter pylori may progress to stomach cancer, and Fusobacterium nucleatum and Enterococcus faecalis have been shown to contribute to colorectal cancer. Those examples differ from a microbiome; this “a community of bacteria and possibly other microscopic bugs, like fungi, that are happily living in the tumor” the same way microbes reside in our guts, he said.
Dr. Knight said that many bacteria his team identified “have been confirmed independently in subsequent work.” He acknowledged, however, that more research is needed.
Several of the contested studies above were among a lengthy list that Dr. Knight provided, noting that most of the disagreements “have two sides to them, and critiques from one particular group does not immediately invalidate a reported finding.”
Yet, many of the papers Dr. Knight listed are precisely the types that skeptics like Dr. Salzberg believe are too flawed to draw reliable conclusions.
“I think many agree that microbes may exist within tumors that are exposed to the environment, like tumors of the skin, gut, and mouth,” Dr. Vujkovic-Cvijin said. It’s less clear, however, whether tumors further from the body’s microbiome harbor any microbes or where they came from if they do. Microbial signals in organs elsewhere in the body become faint quickly, he said.
Underdeveloped Technology
Though Dr. Salzberg said that the concept of a tumor microbiome is “implausible” because there’s no easy route for bacteria to reach internal organs, it’s unclear whether scientists have the technology yet to adequately answer this question.
For one thing, samples in these types of studies are typically “ultra-low biomass samples, where the signal — the amount of microbes in the sample — is so low that it’s comparable to how much would be expected to be found in reagents and environmental contamination through processing,” Dr. Vujkovic-Cvijin explained. Many polymerases used to amplify a DNA signal, for example, are made in bacteria and may retain trace amounts identified in these studies.
Dr. Knight agreed that low biomass is a challenge in this field but is not an unsurmountable one.
Another challenge is that study samples, as with Dr. Knight’s work, were collected during routine surgeries without the intent to find a microbial signal. Simply using a scalpel to cut through the skin means cutting through a layer of bacteria, and surgery rooms are not designed to eliminate all bacteria. Some work has even shown there is a “hospital microbiome,” so “you can easily have that creep into your signal and mistake it for tumor-resident bacteria,” Dr. Vujkovic-Cvijin said.
Dr. Knight asserted that the samples are taken under sterile conditions, but other researchers do not think the level of sterility necessary for completely clean samples is possible.
“Just because it’s in your sample doesn’t mean it was in your tumor,” Dr. Gihawi said.
Even if scientists can retrieve a reliable sample without contamination, analyzing it requires comparing the genetic material to existing databases of microbial genomes. Yet, contamination and misclassification of genetic sequences can be problems in those reference genomes too, Dr. Gihawi explained.
Machine learning algorithms have a role in interpreting data, but “we need to be careful of what we use them for,” he added.
“These techniques are in their infancy, and we’re starting to chase them down, which is why we need to move microbiome research in a way that can be used clinically,” Dr. Gihawi said.
Influence on Cancer Treatment Outcomes
Again, however, the question of whether microbiomes exist within tumors is only one slice of the much larger field looking at microbiomes and cancer, including its influence on cancer treatment outcomes. Although much remains to be learned, less controversy exists over the thousands of studies in the past two decades that have gradually revealed how the body’s microbiome can affect both the course of a cancer and the effectiveness of different treatments.
The growing research showing the importance of the gut microbiome in cancer treatments is not surprising given its role in immunity more broadly. Because the human immune system must recognize and defend against microbes, the microbiome helps train it, Dr. Vujkovic-Cvijin said.
Some bacteria can escape the gut — a phenomenon called bacterial translocation — and may aid in fighting tumors. To grow large enough to be seen on imaging, tumors need to evolve several abilities, such as growing enough vascularization to receive blood flow and shutting down local immune responses.
“Any added boost, like immunotherapy, has a chance of breaking through that immune forcefield and killing the tumor cells,” Dr. Vujkovic-Cvijin said. Escaped gut bacteria may provide that boost.
“There’s a lot of evidence that depletion of the gut microbiome impairs immunotherapy and chemotherapy. The thinking behind some of those studies is that gut microbes can cross the gut barrier and when they do, they activate the immune system,” he said.
In mice engineered to have sterile guts, for example, the lack of bacteria results in less effective immune systems, Dr. Vujkovic-Cvijin pointed out. A host of research has shown that antibiotic exposure during and even 6 months before immunotherapy dramatically reduces survival rates. “That’s pretty convincing to me that gut microbes are important,” he said.
Dr. Vujkovic-Cvijin cautioned that there continues to be controversy on understanding which bacteria are important for response to immunotherapy. “The field is still in its infancy in terms of understanding which bacteria are most important for these effects,” he said.
Dr. Knight suggested that escaped bacteria may be the genesis of the ones that he and other researchers believe exist in tumors. “Because tumor microbes must come from somewhere, it is to be expected that some of those microbes will be co-opted from body-site specific commensals.”
It’s also possible that metabolites released from gut bacteria escape the gut and could theoretically affect distant tumor growth, Dr. Gihawi said. The most promising avenue of research in this area is metabolites being used as biomarkers, added Dr. Gihawi, whose lab published research on a link between bacteria detected in men’s urine and a more aggressive subset of prostate cancers. But that research is not far enough along to develop lab tests for clinical use, he noted.
No Consensus Yet
Even before the controversy erupted around Dr. Knight’s research, he co-founded the company Micronoma to develop cancer tests based on his microbe findings. The company has raised $17.5 million from private investors as of August 2023 and received the US Food and Drug Administration’s Breakthrough Device designation, allowing the firm to fast-track clinical trials testing the technology. The recent critiques have not changed the company’s plans.
It’s safe to say that scientists will continue to research and debate the possibility of tumor microbiomes until a consensus emerges.
“The field is evolving and studies testing the reproducibility of tumor-resident microbial signals are essential for developing our understanding in this area,” Dr. Vujkovic-Cvijin said.
Even if that path ultimately leads nowhere, as Dr. Salzberg expects, research into microbiomes and cancer has plenty of other directions to go.
“I’m actually quite an optimist,” Dr. Gihawi said. “I think there’s a lot of scope for some really good research here, especially in the sites where we know there is a strong microbiome, such as the gastrointestinal tract.”
A version of this article appeared on Medscape.com.