Colon and Rectal

A short course of radiation therapy followed by neoadjuvant chemotherapy resulted in a clinical complete response (CR) in almost half of 90 patients with locally advanced rectal cancer, allowing the majority of responders to skip surgical resection, a retrospective study indicates.

Specifically, at a median follow-up of 16.6 months for living patients, the initial clinical CR rate was 48% overall.

“While we do not have enough follow-up yet to know the late side-effect profile of this regimen, our preliminary results are promising,” Re-I Chin, MD, of Washington University School of Medicine, St. Louis, Missouri, told Medscape Medical News in an email.

The study was presented at the virtual 2020 meeting of the American Society of Radiation Oncology (ASTRO).

“Certainly, longer follow-up will be needed in this study, but none of the observed patients to date has experienced an unsalvageable failure,” said meeting discussant Amol Narang, MD, of Johns Hopkins University, Baltimore, Maryland.

He reminded conference attendees that, despite good evidence supporting equivalency in oncologic outcomes between short-course radiation and long-course chemoradiation, the former is “highly underutilized in the US” with a mere 1% usage rate between 2004 and 2014.

The current study’s short-course treatment approach was compared in this setting to long-course chemoradiation and adjuvant chemotherapy in the RAPIDO trial reported at the 2020 annual meeting of the American Society of Clinical Oncology (ASCO), Narang pointed out.

Short-course patients had a higher rate of pathological complete response (pCR) and a lower rate of treatment failure compared with patients who received long-course chemoradiation and adjuvant chemotherapy; both patient groups underwent total mesorectal excision — which is different from the current analysis. The RAPIDO investigators concluded that the approach featuring the short course “can be considered as a new standard of care.”

Narang said the data collectively “begs the question as to whether the superiority of long-course chemoradiation should really have to be demonstrated to justify its use.”

But Chin highlighted toxicity issues. “Historically, there have been concerns regarding toxicity with short-course radiation therapy since it requires larger doses of radiation given over a shorter period of time,” Chin explained. “But [the short course] is particularly convenient for patients since it saves them more than a month of daily trips to the radiation oncology department.”
 

Seven local failures

The single-center study involved patients with newly diagnosed, nonmetastatic rectal adenocarcinoma treated with short-course radiation therapy followed by chemotherapy in 2018 and 2019. Nearly all (96%) had locally advanced disease, with either a T3/T4 tumor or node-positive disease. Median tumor size was 4.6 cm.

“Many of the patients in the study had low lying tumors,” Chin reported, with a median distance from the anal verge of 7 cm.

Radiation therapy was delivered in 25 Gy given in five fractions over 5 consecutive days, with the option to boost the dose to 30 Gy or 35 Gy in five fractions if extra-mesorectal lymph nodes were involved. Conventional 3D or intensity-modulated radiation was used and all patients completed treatment.

The median interval between diagnosis of rectal cancer and initiation of radiation therapy was 1.4 months, while the median interval between completion of radiation to initiation of chemotherapy was 2.7 weeks.

The most common chemotherapy regimen was FOLFOX – consisting of leucovorin, fluorouracil (5-FU), and oxaliplatin – or modified FOLFOX. For patients who received six or more cycles of chemotherapy, the median time spent on treatment was 3.9 months.

For those who completed at least six cycles of chemotherapy, the overall clinical CR was 51%, and, for patients with locally advanced disease, the clinical CR rate was 49%. Five of the 43 patients who achieved an initial clinical CR still underwent surgical resection because of patient or physician preference. Among this small group of patients, 4 of the 5 achieved a pCR, and the remaining patient achieved a pathological partial response (pPR).

A total of 42 patients (47% of the group) achieved a partial response following the radiation plus chemotherapy paradigm, and one patient had progressive disease. All underwent surgical resection. One patient did not complete chemotherapy and did not get surgery and subsequently died.

This left 38 patients to be managed nonoperatively. In this nonoperative cohort, 79% of patients continued to have a clinical CR at the end of follow-up. Of the 7 patients with local failure, 6 were salvaged by surgery, one was salvaged by chemotherapy, and all 7 treatment failures had no evidence of disease at last follow-up.

Of the small group of 5 patients who achieved an initial clinical CR following short-course radiation therapy and neoadjuvant chemotherapy, there were no further events in this group, whereas, for patients who achieved only an initial partial response or who had progressive disease, 72% remained event-free.

Approximately half of those who achieved a clinical CR to the treatment regimen had no late gastrointestinal toxicities, and no grade 3 or 4 toxicities were observed. “Surgical resection of tumors — even without a permanent stoma — can result in significantly decreased bowel function, so our goal is to treat patients without surgery and maintain good bowel function,” Chin noted.

“For rectal cancer, both short-course radiation therapy and nonoperative management are emerging treatment paradigms that may be more cost-effective and convenient compared to long-course chemoradiation followed by surgery, [especially since] the COVID-19 pandemic...has spurred changes in clinical practices in radiation oncology,” she said.

Chin has disclosed no relevant financial relationships. Narang reports receiving research support from Boston Scientific.
 

This article first appeared on Medscape.com.

A short course of radiation therapy followed by neoadjuvant chemotherapy resulted in a clinical complete response (CR) in almost half of 90 patients with locally advanced rectal cancer, allowing the majority of responders to skip surgical resection, a retrospective study indicates.

Specifically, at a median follow-up of 16.6 months for living patients, the initial clinical CR rate was 48% overall.

“While we do not have enough follow-up yet to know the late side-effect profile of this regimen, our preliminary results are promising,” Re-I Chin, MD, of Washington University School of Medicine, St. Louis, Missouri, told Medscape Medical News in an email.

The study was presented at the virtual 2020 meeting of the American Society of Radiation Oncology (ASTRO).

“Certainly, longer follow-up will be needed in this study, but none of the observed patients to date has experienced an unsalvageable failure,” said meeting discussant Amol Narang, MD, of Johns Hopkins University, Baltimore, Maryland.

He reminded conference attendees that, despite good evidence supporting equivalency in oncologic outcomes between short-course radiation and long-course chemoradiation, the former is “highly underutilized in the US” with a mere 1% usage rate between 2004 and 2014.

The current study’s short-course treatment approach was compared in this setting to long-course chemoradiation and adjuvant chemotherapy in the RAPIDO trial reported at the 2020 annual meeting of the American Society of Clinical Oncology (ASCO), Narang pointed out.

Short-course patients had a higher rate of pathological complete response (pCR) and a lower rate of treatment failure compared with patients who received long-course chemoradiation and adjuvant chemotherapy; both patient groups underwent total mesorectal excision — which is different from the current analysis. The RAPIDO investigators concluded that the approach featuring the short course “can be considered as a new standard of care.”

Narang said the data collectively “begs the question as to whether the superiority of long-course chemoradiation should really have to be demonstrated to justify its use.”

But Chin highlighted toxicity issues. “Historically, there have been concerns regarding toxicity with short-course radiation therapy since it requires larger doses of radiation given over a shorter period of time,” Chin explained. “But [the short course] is particularly convenient for patients since it saves them more than a month of daily trips to the radiation oncology department.”
 

Seven local failures

The single-center study involved patients with newly diagnosed, nonmetastatic rectal adenocarcinoma treated with short-course radiation therapy followed by chemotherapy in 2018 and 2019. Nearly all (96%) had locally advanced disease, with either a T3/T4 tumor or node-positive disease. Median tumor size was 4.6 cm.

“Many of the patients in the study had low lying tumors,” Chin reported, with a median distance from the anal verge of 7 cm.

Radiation therapy was delivered in 25 Gy given in five fractions over 5 consecutive days, with the option to boost the dose to 30 Gy or 35 Gy in five fractions if extra-mesorectal lymph nodes were involved. Conventional 3D or intensity-modulated radiation was used and all patients completed treatment.

The median interval between diagnosis of rectal cancer and initiation of radiation therapy was 1.4 months, while the median interval between completion of radiation to initiation of chemotherapy was 2.7 weeks.

The most common chemotherapy regimen was FOLFOX – consisting of leucovorin, fluorouracil (5-FU), and oxaliplatin – or modified FOLFOX. For patients who received six or more cycles of chemotherapy, the median time spent on treatment was 3.9 months.

For those who completed at least six cycles of chemotherapy, the overall clinical CR was 51%, and, for patients with locally advanced disease, the clinical CR rate was 49%. Five of the 43 patients who achieved an initial clinical CR still underwent surgical resection because of patient or physician preference. Among this small group of patients, 4 of the 5 achieved a pCR, and the remaining patient achieved a pathological partial response (pPR).

A total of 42 patients (47% of the group) achieved a partial response following the radiation plus chemotherapy paradigm, and one patient had progressive disease. All underwent surgical resection. One patient did not complete chemotherapy and did not get surgery and subsequently died.

This left 38 patients to be managed nonoperatively. In this nonoperative cohort, 79% of patients continued to have a clinical CR at the end of follow-up. Of the 7 patients with local failure, 6 were salvaged by surgery, one was salvaged by chemotherapy, and all 7 treatment failures had no evidence of disease at last follow-up.

Of the small group of 5 patients who achieved an initial clinical CR following short-course radiation therapy and neoadjuvant chemotherapy, there were no further events in this group, whereas, for patients who achieved only an initial partial response or who had progressive disease, 72% remained event-free.

Approximately half of those who achieved a clinical CR to the treatment regimen had no late gastrointestinal toxicities, and no grade 3 or 4 toxicities were observed. “Surgical resection of tumors — even without a permanent stoma — can result in significantly decreased bowel function, so our goal is to treat patients without surgery and maintain good bowel function,” Chin noted.

“For rectal cancer, both short-course radiation therapy and nonoperative management are emerging treatment paradigms that may be more cost-effective and convenient compared to long-course chemoradiation followed by surgery, [especially since] the COVID-19 pandemic...has spurred changes in clinical practices in radiation oncology,” she said.

Chin has disclosed no relevant financial relationships. Narang reports receiving research support from Boston Scientific.
 

This article first appeared on Medscape.com.

A short course of radiation therapy followed by neoadjuvant chemotherapy resulted in a clinical complete response (CR) in almost half of 90 patients with locally advanced rectal cancer, allowing the majority of responders to skip surgical resection, a retrospective study indicates.

Specifically, at a median follow-up of 16.6 months for living patients, the initial clinical CR rate was 48% overall.

“While we do not have enough follow-up yet to know the late side-effect profile of this regimen, our preliminary results are promising,” Re-I Chin, MD, of Washington University School of Medicine, St. Louis, Missouri, told Medscape Medical News in an email.

The study was presented at the virtual 2020 meeting of the American Society of Radiation Oncology (ASTRO).

“Certainly, longer follow-up will be needed in this study, but none of the observed patients to date has experienced an unsalvageable failure,” said meeting discussant Amol Narang, MD, of Johns Hopkins University, Baltimore, Maryland.

He reminded conference attendees that, despite good evidence supporting equivalency in oncologic outcomes between short-course radiation and long-course chemoradiation, the former is “highly underutilized in the US” with a mere 1% usage rate between 2004 and 2014.

The current study’s short-course treatment approach was compared in this setting to long-course chemoradiation and adjuvant chemotherapy in the RAPIDO trial reported at the 2020 annual meeting of the American Society of Clinical Oncology (ASCO), Narang pointed out.

Short-course patients had a higher rate of pathological complete response (pCR) and a lower rate of treatment failure compared with patients who received long-course chemoradiation and adjuvant chemotherapy; both patient groups underwent total mesorectal excision — which is different from the current analysis. The RAPIDO investigators concluded that the approach featuring the short course “can be considered as a new standard of care.”

Narang said the data collectively “begs the question as to whether the superiority of long-course chemoradiation should really have to be demonstrated to justify its use.”

But Chin highlighted toxicity issues. “Historically, there have been concerns regarding toxicity with short-course radiation therapy since it requires larger doses of radiation given over a shorter period of time,” Chin explained. “But [the short course] is particularly convenient for patients since it saves them more than a month of daily trips to the radiation oncology department.”
 

Seven local failures

The single-center study involved patients with newly diagnosed, nonmetastatic rectal adenocarcinoma treated with short-course radiation therapy followed by chemotherapy in 2018 and 2019. Nearly all (96%) had locally advanced disease, with either a T3/T4 tumor or node-positive disease. Median tumor size was 4.6 cm.

“Many of the patients in the study had low lying tumors,” Chin reported, with a median distance from the anal verge of 7 cm.

Radiation therapy was delivered in 25 Gy given in five fractions over 5 consecutive days, with the option to boost the dose to 30 Gy or 35 Gy in five fractions if extra-mesorectal lymph nodes were involved. Conventional 3D or intensity-modulated radiation was used and all patients completed treatment.

The median interval between diagnosis of rectal cancer and initiation of radiation therapy was 1.4 months, while the median interval between completion of radiation to initiation of chemotherapy was 2.7 weeks.

The most common chemotherapy regimen was FOLFOX – consisting of leucovorin, fluorouracil (5-FU), and oxaliplatin – or modified FOLFOX. For patients who received six or more cycles of chemotherapy, the median time spent on treatment was 3.9 months.

For those who completed at least six cycles of chemotherapy, the overall clinical CR was 51%, and, for patients with locally advanced disease, the clinical CR rate was 49%. Five of the 43 patients who achieved an initial clinical CR still underwent surgical resection because of patient or physician preference. Among this small group of patients, 4 of the 5 achieved a pCR, and the remaining patient achieved a pathological partial response (pPR).

A total of 42 patients (47% of the group) achieved a partial response following the radiation plus chemotherapy paradigm, and one patient had progressive disease. All underwent surgical resection. One patient did not complete chemotherapy and did not get surgery and subsequently died.

This left 38 patients to be managed nonoperatively. In this nonoperative cohort, 79% of patients continued to have a clinical CR at the end of follow-up. Of the 7 patients with local failure, 6 were salvaged by surgery, one was salvaged by chemotherapy, and all 7 treatment failures had no evidence of disease at last follow-up.

Of the small group of 5 patients who achieved an initial clinical CR following short-course radiation therapy and neoadjuvant chemotherapy, there were no further events in this group, whereas, for patients who achieved only an initial partial response or who had progressive disease, 72% remained event-free.

Approximately half of those who achieved a clinical CR to the treatment regimen had no late gastrointestinal toxicities, and no grade 3 or 4 toxicities were observed. “Surgical resection of tumors — even without a permanent stoma — can result in significantly decreased bowel function, so our goal is to treat patients without surgery and maintain good bowel function,” Chin noted.

“For rectal cancer, both short-course radiation therapy and nonoperative management are emerging treatment paradigms that may be more cost-effective and convenient compared to long-course chemoradiation followed by surgery, [especially since] the COVID-19 pandemic...has spurred changes in clinical practices in radiation oncology,” she said.

Chin has disclosed no relevant financial relationships. Narang reports receiving research support from Boston Scientific.
 

This article first appeared on Medscape.com.

Screening for colorectal cancer (CRC) should begin at age 45 years instead of 50 years, as recommended in the current guideline, the US Preventive Services Task Force (USPSTF) said in a draft recommendation that is open for public comment.

“This is the only change that was made,” said task force member Michael Barry, MD, director of the Informed Medical Decisions Program in the Health Decision Sciences Center at Massachusetts General Hospital, Boston.

The recommendation is that all adults aged 45-75 years be screened for CRC.

This is an “A” recommendation for adults aged 50-75 and a “B” recommendation for adults aged 45-49. Dr. Barry explained that the reason for this difference is that the benefit is smaller for the 45- to 49-years age group. “But there’s not much difference between A and B from a practical standpoint,” he explained.

For adults aged 76-85, the benefits and harms of screening need to be weighed against the individual’s overall health and personal circumstances. This is a “C” recommendation.

Barry emphasized that the USPSTF document is not final. The draft recommendation and supporting evidence is posted on the task force website and will be available for public comments until Nov. 23.
 

Mounting pressure

The move comes after mounting evidence of an increase in CRC among younger adults and mounting pressure to lower the starting age.

Two years ago, the American Cancer Society (ACS) revised its own screening guidelines and lowered the starting age to 45 years. Soon afterward, a coalition of 22 public health and patient advocacy groups joined the ACS in submitting a letter to the USPSTF asking that the task force reconsider its 2016 guidance (which recommends starting at age 50 years).

The starting age for screening is an important issue, commented Judy Yee, MD, chair of radiology at the Albert Einstein College of Medicine and the Montefiore Health System in New York and chair of the Colon Cancer Committee of the American College of Radiology.

“Right now it is very confusing to physicians and to the public,” Dr. Yee said in an interview at that time. “The USPSTF and the ACS differ as far as the age to begin screening, and insurers may not cover the cost of colorectal cancer screening before age 50.”

Dr. Barry said that the Task Force took notice of recent data showing an increase in the incidence of CRC among younger adults. “The risk now for age 45 to 49 is pretty similar to the risk for people in their early 50s. So in some ways, today’s late 40-year-olds are like yesterday’s 50-year-olds,” he commented.

The task force used simulation models that confirmed what the epidemiologic data suggested and “that we could prevent some additional colorectal cancer deaths by starting screening at age 45,” he said.

The rest of the new draft recommendation is similar to the 2016 guidelines, in which the task force says there is convincing evidence that CRC screening substantially reduces disease-related mortality. However, it does not recommend any one screening approach over another. It recommends both direct visualization, such as colonoscopy, as well as noninvasive stool-based tests. It does not recommend serum tests, urine tests, or capsule endoscopy because there is not yet enough evidence about the benefits and harms of these tests.

“The right test is the one a patient will do,” Dr. Barry commented.

Defining populations

CRC in young adults made the news in August 2020 when Chadwick Boseman, known for his role as King T’Challa in Marvel’s “Black Panther,” died of colon cancer. Diagnosed in 2016, he was only 43 years old.

“The recent passing of Chadwick Boseman is tragic, and our thoughts are with his loved ones during this difficult time,” said Dr. Barry. “As a Black man, the data show that Chadwick was at higher risk for developing colorectal cancer.”

Unfortunately, there is currently not enough evidence that screening Black men younger than 45 could help prevent tragic deaths such as Chadwick’s, he commented. “The task force is calling for more research on colorectal cancer screening in Black adults,” he added.
 

Limit screening to those at higher risk

In contrast to the USPSTF and ACS guidelines, which recommend screening for CRC for everyone over a certain age, a set of recommendations developed by an international panel of experts suggests screening only for individuals who are at higher risk for CRC.

As previously reported, these guidelines suggest restricting screening to adults whose cumulative cancer risk is 3% or more in the next 15 years, the point at which the balance between benefits and harms favors screening.

The authors, led by Lise Helsingen, MD, Clinical Effectiveness Research Group, University of Oslo, said “the optimal choice for each person requires shared decision-making.”

Such a risk-based approach is “increasingly regarded as the most appropriate way to discuss cancer screening.” That approach is already used in prostate and lung cancer screening, they noted.
 

A version of this article originally appeared on Medscape.com.

Screening for colorectal cancer (CRC) should begin at age 45 years instead of 50 years, as recommended in the current guideline, the US Preventive Services Task Force (USPSTF) said in a draft recommendation that is open for public comment.

“This is the only change that was made,” said task force member Michael Barry, MD, director of the Informed Medical Decisions Program in the Health Decision Sciences Center at Massachusetts General Hospital, Boston.

The recommendation is that all adults aged 45-75 years be screened for CRC.

This is an “A” recommendation for adults aged 50-75 and a “B” recommendation for adults aged 45-49. Dr. Barry explained that the reason for this difference is that the benefit is smaller for the 45- to 49-years age group. “But there’s not much difference between A and B from a practical standpoint,” he explained.

For adults aged 76-85, the benefits and harms of screening need to be weighed against the individual’s overall health and personal circumstances. This is a “C” recommendation.

Barry emphasized that the USPSTF document is not final. The draft recommendation and supporting evidence is posted on the task force website and will be available for public comments until Nov. 23.
 

Mounting pressure

The move comes after mounting evidence of an increase in CRC among younger adults and mounting pressure to lower the starting age.

Two years ago, the American Cancer Society (ACS) revised its own screening guidelines and lowered the starting age to 45 years. Soon afterward, a coalition of 22 public health and patient advocacy groups joined the ACS in submitting a letter to the USPSTF asking that the task force reconsider its 2016 guidance (which recommends starting at age 50 years).

The starting age for screening is an important issue, commented Judy Yee, MD, chair of radiology at the Albert Einstein College of Medicine and the Montefiore Health System in New York and chair of the Colon Cancer Committee of the American College of Radiology.

“Right now it is very confusing to physicians and to the public,” Dr. Yee said in an interview at that time. “The USPSTF and the ACS differ as far as the age to begin screening, and insurers may not cover the cost of colorectal cancer screening before age 50.”

Dr. Barry said that the Task Force took notice of recent data showing an increase in the incidence of CRC among younger adults. “The risk now for age 45 to 49 is pretty similar to the risk for people in their early 50s. So in some ways, today’s late 40-year-olds are like yesterday’s 50-year-olds,” he commented.

The task force used simulation models that confirmed what the epidemiologic data suggested and “that we could prevent some additional colorectal cancer deaths by starting screening at age 45,” he said.

The rest of the new draft recommendation is similar to the 2016 guidelines, in which the task force says there is convincing evidence that CRC screening substantially reduces disease-related mortality. However, it does not recommend any one screening approach over another. It recommends both direct visualization, such as colonoscopy, as well as noninvasive stool-based tests. It does not recommend serum tests, urine tests, or capsule endoscopy because there is not yet enough evidence about the benefits and harms of these tests.

“The right test is the one a patient will do,” Dr. Barry commented.

Defining populations

CRC in young adults made the news in August 2020 when Chadwick Boseman, known for his role as King T’Challa in Marvel’s “Black Panther,” died of colon cancer. Diagnosed in 2016, he was only 43 years old.

“The recent passing of Chadwick Boseman is tragic, and our thoughts are with his loved ones during this difficult time,” said Dr. Barry. “As a Black man, the data show that Chadwick was at higher risk for developing colorectal cancer.”

Unfortunately, there is currently not enough evidence that screening Black men younger than 45 could help prevent tragic deaths such as Chadwick’s, he commented. “The task force is calling for more research on colorectal cancer screening in Black adults,” he added.
 

Limit screening to those at higher risk

In contrast to the USPSTF and ACS guidelines, which recommend screening for CRC for everyone over a certain age, a set of recommendations developed by an international panel of experts suggests screening only for individuals who are at higher risk for CRC.

As previously reported, these guidelines suggest restricting screening to adults whose cumulative cancer risk is 3% or more in the next 15 years, the point at which the balance between benefits and harms favors screening.

The authors, led by Lise Helsingen, MD, Clinical Effectiveness Research Group, University of Oslo, said “the optimal choice for each person requires shared decision-making.”

Such a risk-based approach is “increasingly regarded as the most appropriate way to discuss cancer screening.” That approach is already used in prostate and lung cancer screening, they noted.
 

A version of this article originally appeared on Medscape.com.

Screening for colorectal cancer (CRC) should begin at age 45 years instead of 50 years, as recommended in the current guideline, the US Preventive Services Task Force (USPSTF) said in a draft recommendation that is open for public comment.

“This is the only change that was made,” said task force member Michael Barry, MD, director of the Informed Medical Decisions Program in the Health Decision Sciences Center at Massachusetts General Hospital, Boston.

The recommendation is that all adults aged 45-75 years be screened for CRC.

This is an “A” recommendation for adults aged 50-75 and a “B” recommendation for adults aged 45-49. Dr. Barry explained that the reason for this difference is that the benefit is smaller for the 45- to 49-years age group. “But there’s not much difference between A and B from a practical standpoint,” he explained.

For adults aged 76-85, the benefits and harms of screening need to be weighed against the individual’s overall health and personal circumstances. This is a “C” recommendation.

Barry emphasized that the USPSTF document is not final. The draft recommendation and supporting evidence is posted on the task force website and will be available for public comments until Nov. 23.
 

Mounting pressure

The move comes after mounting evidence of an increase in CRC among younger adults and mounting pressure to lower the starting age.

Two years ago, the American Cancer Society (ACS) revised its own screening guidelines and lowered the starting age to 45 years. Soon afterward, a coalition of 22 public health and patient advocacy groups joined the ACS in submitting a letter to the USPSTF asking that the task force reconsider its 2016 guidance (which recommends starting at age 50 years).

The starting age for screening is an important issue, commented Judy Yee, MD, chair of radiology at the Albert Einstein College of Medicine and the Montefiore Health System in New York and chair of the Colon Cancer Committee of the American College of Radiology.

“Right now it is very confusing to physicians and to the public,” Dr. Yee said in an interview at that time. “The USPSTF and the ACS differ as far as the age to begin screening, and insurers may not cover the cost of colorectal cancer screening before age 50.”

Dr. Barry said that the Task Force took notice of recent data showing an increase in the incidence of CRC among younger adults. “The risk now for age 45 to 49 is pretty similar to the risk for people in their early 50s. So in some ways, today’s late 40-year-olds are like yesterday’s 50-year-olds,” he commented.

The task force used simulation models that confirmed what the epidemiologic data suggested and “that we could prevent some additional colorectal cancer deaths by starting screening at age 45,” he said.

The rest of the new draft recommendation is similar to the 2016 guidelines, in which the task force says there is convincing evidence that CRC screening substantially reduces disease-related mortality. However, it does not recommend any one screening approach over another. It recommends both direct visualization, such as colonoscopy, as well as noninvasive stool-based tests. It does not recommend serum tests, urine tests, or capsule endoscopy because there is not yet enough evidence about the benefits and harms of these tests.

“The right test is the one a patient will do,” Dr. Barry commented.

Defining populations

CRC in young adults made the news in August 2020 when Chadwick Boseman, known for his role as King T’Challa in Marvel’s “Black Panther,” died of colon cancer. Diagnosed in 2016, he was only 43 years old.

“The recent passing of Chadwick Boseman is tragic, and our thoughts are with his loved ones during this difficult time,” said Dr. Barry. “As a Black man, the data show that Chadwick was at higher risk for developing colorectal cancer.”

Unfortunately, there is currently not enough evidence that screening Black men younger than 45 could help prevent tragic deaths such as Chadwick’s, he commented. “The task force is calling for more research on colorectal cancer screening in Black adults,” he added.
 

Limit screening to those at higher risk

In contrast to the USPSTF and ACS guidelines, which recommend screening for CRC for everyone over a certain age, a set of recommendations developed by an international panel of experts suggests screening only for individuals who are at higher risk for CRC.

As previously reported, these guidelines suggest restricting screening to adults whose cumulative cancer risk is 3% or more in the next 15 years, the point at which the balance between benefits and harms favors screening.

The authors, led by Lise Helsingen, MD, Clinical Effectiveness Research Group, University of Oslo, said “the optimal choice for each person requires shared decision-making.”

Such a risk-based approach is “increasingly regarded as the most appropriate way to discuss cancer screening.” That approach is already used in prostate and lung cancer screening, they noted.
 

A version of this article originally appeared on Medscape.com.

Intensive surveillance with carcinoembryonic antigen (CEA) testing and CT scans after colorectal cancer resection did not improve recurrence-free or overall survival when compared with standard abdominal ultrasound and chest x-ray monitoring in a phase 3 trial of almost 2,000 patients.

However, among patients with colon cancer recurrence, those randomized to intensive surveillance more often had a second surgery with curative intent. Even so, there was no overall survival benefit versus standard surveillance in this group.

In short, “none of the follow-up modalities resulted in a difference,” said investigator Come Lepage, MD, PhD, of Centre Hospitalier Universitaire de Dijon (France).

Dr. Lepage presented these findings at the European Society for Medical Oncology Virtual Congress 2020.

Dr. Lepage said the study’s results suggest guidelines that include CT and CEA monitoring should be amended, and the standard surveillance methods should be ultrasound and chest x-ray. Dr. LePage called CEA surveillance “useless” and said CT scans should be performed only in cases of suspected recurrence.

However, study discussant Tim Price, MBBS, DHSc, of the University of Adelaide, noted that both the intensive and standard arms in this study had abdominal imaging every 3 months, be it ultrasound or CT, so even in the standard arms, surveillance “was still fairly aggressive.”

Because of that, the study does not “suggest we should decrease our intensity,” Dr. Price said.

He added that the study’s major finding was that more intensive surveillance led to higher rates of secondary surgery with curative intent, probably because recurrences were caught earlier than they would have been with standard surveillance, when curative surgery was still possible.

Patients in the study were treated during 2009-2015, and that might have also made a difference. “We need to remember that, in 2020, care is very different,” Dr. Price said. This includes increased surgical interventions and options for oligometastatic disease, plus systemic therapies such as pembrolizumab. With modern treatments, detecting recurrences earlier “may well have an impact on survival.”

Perhaps patients would live longer with “earlier diagnosis in today’s setting with more active agents and more aggressive surgery and radiotherapy [e.g., stereotactic ablative radiation therapy],” Dr. Price said in an interview.
 

Study details

The trial, dubbed PRODIGE 13, was done to bring clarity to the surveillance issue. Intensive follow-up after curative surgery for colorectal cancer, including CT and CEA monitoring, is recommended by various scientific societies, but it’s based mainly on expert opinion. Results of the few clinical trials on the issue have been controversial, Dr. Lepage explained.

PRODIGE 13 included 1,995 subjects with colorectal cancer. About half of patients had stage II disease, and the other half had stage III. Most patients were 75 years or younger at baseline, and there were more men in the study than women. All patients underwent resection with curative intent and had no evidence of residual disease 3 months after surgery. Some patients received adjuvant chemotherapy.

Patients were first randomized to no CEA monitoring or CEA monitoring every 3 months for the first 2 years, then every 6 months for an additional 3 years. Members in both groups were then randomized a second time to either intensive or standard radiologic surveillance.

Surveillance in the standard arm consisted of an abdominal ultrasound every 3 months for the first 3 years, then biannually for an additional 2 years, plus chest x-rays every 6 months for 5 years. Intensive surveillance consisted of CT imaging, including thoracic imaging, alternating with abdominal ultrasound, every 3 months, then biannually for another 2 years.

At baseline, the surveillance groups were well balanced with regard to demographics, primary tumor location, and other factors, but stage III disease was more prevalent among patients randomized to standard radiologic monitoring without CEA.
 

Results

The median follow up was 6.5 years. There were no significant differences between the surveillance groups with regard to 5-year overall survival (P = .340) or recurrence-free survival (P = .473).

There were no significant differences in recurrence-free or overall survival when patients were stratified by age, sex, stage, CEA at a cut point of 5 mcg/L, and primary tumor characteristics including location, perineural invasion, and occlusion/perforation.

There were 356 recurrences in patients initially treated for colon cancer. CEA surveillance with or without CT scan was associated with an increased incidence of secondary resection with curative intent. The rate of secondary resection was 66.3% in the standard imaging with CEA arm, 59.5% in the CT plus CEA arm, 50.7% with CT imaging but no CEA, and 40.9% with standard imaging and no CEA (P = .0035).

The rates were similar among the 83 patients with recurrence after initial treatment for rectal cancer, but the between-arm differences were not significant. The rate of secondary resection with curative intent was 57.9% in the standard imaging with CEA arm, 47.8% in the CT plus CEA arm, 55% with CT imaging but no CEA, and 42.9% with standard imaging and no CEA.

The research is ongoing, and the team expects to report on secondary outcomes and ancillary studies of circulating tumor DNA, among other things, in 2021.

The study is being funded by the Federation Francophone de Cancerologie Digestive. Dr. Lepage disclosed ties with Novartis, Amgen, Bayer, Servier, and AAA. Dr. Price disclosed institutional research funding from Amgen and being an uncompensated adviser to Pierre-Fabre and Merck.

[email protected]

SOURCE: Lepage C et al. ESMO 2020, Abstract 398O.

Intensive surveillance with carcinoembryonic antigen (CEA) testing and CT scans after colorectal cancer resection did not improve recurrence-free or overall survival when compared with standard abdominal ultrasound and chest x-ray monitoring in a phase 3 trial of almost 2,000 patients.

However, among patients with colon cancer recurrence, those randomized to intensive surveillance more often had a second surgery with curative intent. Even so, there was no overall survival benefit versus standard surveillance in this group.

In short, “none of the follow-up modalities resulted in a difference,” said investigator Come Lepage, MD, PhD, of Centre Hospitalier Universitaire de Dijon (France).

Dr. Lepage presented these findings at the European Society for Medical Oncology Virtual Congress 2020.

Dr. Lepage said the study’s results suggest guidelines that include CT and CEA monitoring should be amended, and the standard surveillance methods should be ultrasound and chest x-ray. Dr. LePage called CEA surveillance “useless” and said CT scans should be performed only in cases of suspected recurrence.

However, study discussant Tim Price, MBBS, DHSc, of the University of Adelaide, noted that both the intensive and standard arms in this study had abdominal imaging every 3 months, be it ultrasound or CT, so even in the standard arms, surveillance “was still fairly aggressive.”

Because of that, the study does not “suggest we should decrease our intensity,” Dr. Price said.

He added that the study’s major finding was that more intensive surveillance led to higher rates of secondary surgery with curative intent, probably because recurrences were caught earlier than they would have been with standard surveillance, when curative surgery was still possible.

Patients in the study were treated during 2009-2015, and that might have also made a difference. “We need to remember that, in 2020, care is very different,” Dr. Price said. This includes increased surgical interventions and options for oligometastatic disease, plus systemic therapies such as pembrolizumab. With modern treatments, detecting recurrences earlier “may well have an impact on survival.”

Perhaps patients would live longer with “earlier diagnosis in today’s setting with more active agents and more aggressive surgery and radiotherapy [e.g., stereotactic ablative radiation therapy],” Dr. Price said in an interview.
 

Study details

The trial, dubbed PRODIGE 13, was done to bring clarity to the surveillance issue. Intensive follow-up after curative surgery for colorectal cancer, including CT and CEA monitoring, is recommended by various scientific societies, but it’s based mainly on expert opinion. Results of the few clinical trials on the issue have been controversial, Dr. Lepage explained.

PRODIGE 13 included 1,995 subjects with colorectal cancer. About half of patients had stage II disease, and the other half had stage III. Most patients were 75 years or younger at baseline, and there were more men in the study than women. All patients underwent resection with curative intent and had no evidence of residual disease 3 months after surgery. Some patients received adjuvant chemotherapy.

Patients were first randomized to no CEA monitoring or CEA monitoring every 3 months for the first 2 years, then every 6 months for an additional 3 years. Members in both groups were then randomized a second time to either intensive or standard radiologic surveillance.

Surveillance in the standard arm consisted of an abdominal ultrasound every 3 months for the first 3 years, then biannually for an additional 2 years, plus chest x-rays every 6 months for 5 years. Intensive surveillance consisted of CT imaging, including thoracic imaging, alternating with abdominal ultrasound, every 3 months, then biannually for another 2 years.

At baseline, the surveillance groups were well balanced with regard to demographics, primary tumor location, and other factors, but stage III disease was more prevalent among patients randomized to standard radiologic monitoring without CEA.
 

Results

The median follow up was 6.5 years. There were no significant differences between the surveillance groups with regard to 5-year overall survival (P = .340) or recurrence-free survival (P = .473).

There were no significant differences in recurrence-free or overall survival when patients were stratified by age, sex, stage, CEA at a cut point of 5 mcg/L, and primary tumor characteristics including location, perineural invasion, and occlusion/perforation.

There were 356 recurrences in patients initially treated for colon cancer. CEA surveillance with or without CT scan was associated with an increased incidence of secondary resection with curative intent. The rate of secondary resection was 66.3% in the standard imaging with CEA arm, 59.5% in the CT plus CEA arm, 50.7% with CT imaging but no CEA, and 40.9% with standard imaging and no CEA (P = .0035).

The rates were similar among the 83 patients with recurrence after initial treatment for rectal cancer, but the between-arm differences were not significant. The rate of secondary resection with curative intent was 57.9% in the standard imaging with CEA arm, 47.8% in the CT plus CEA arm, 55% with CT imaging but no CEA, and 42.9% with standard imaging and no CEA.

The research is ongoing, and the team expects to report on secondary outcomes and ancillary studies of circulating tumor DNA, among other things, in 2021.

The study is being funded by the Federation Francophone de Cancerologie Digestive. Dr. Lepage disclosed ties with Novartis, Amgen, Bayer, Servier, and AAA. Dr. Price disclosed institutional research funding from Amgen and being an uncompensated adviser to Pierre-Fabre and Merck.

[email protected]

SOURCE: Lepage C et al. ESMO 2020, Abstract 398O.

Intensive surveillance with carcinoembryonic antigen (CEA) testing and CT scans after colorectal cancer resection did not improve recurrence-free or overall survival when compared with standard abdominal ultrasound and chest x-ray monitoring in a phase 3 trial of almost 2,000 patients.

However, among patients with colon cancer recurrence, those randomized to intensive surveillance more often had a second surgery with curative intent. Even so, there was no overall survival benefit versus standard surveillance in this group.

In short, “none of the follow-up modalities resulted in a difference,” said investigator Come Lepage, MD, PhD, of Centre Hospitalier Universitaire de Dijon (France).

Dr. Lepage presented these findings at the European Society for Medical Oncology Virtual Congress 2020.

Dr. Lepage said the study’s results suggest guidelines that include CT and CEA monitoring should be amended, and the standard surveillance methods should be ultrasound and chest x-ray. Dr. LePage called CEA surveillance “useless” and said CT scans should be performed only in cases of suspected recurrence.

However, study discussant Tim Price, MBBS, DHSc, of the University of Adelaide, noted that both the intensive and standard arms in this study had abdominal imaging every 3 months, be it ultrasound or CT, so even in the standard arms, surveillance “was still fairly aggressive.”

Because of that, the study does not “suggest we should decrease our intensity,” Dr. Price said.

He added that the study’s major finding was that more intensive surveillance led to higher rates of secondary surgery with curative intent, probably because recurrences were caught earlier than they would have been with standard surveillance, when curative surgery was still possible.

Patients in the study were treated during 2009-2015, and that might have also made a difference. “We need to remember that, in 2020, care is very different,” Dr. Price said. This includes increased surgical interventions and options for oligometastatic disease, plus systemic therapies such as pembrolizumab. With modern treatments, detecting recurrences earlier “may well have an impact on survival.”

Perhaps patients would live longer with “earlier diagnosis in today’s setting with more active agents and more aggressive surgery and radiotherapy [e.g., stereotactic ablative radiation therapy],” Dr. Price said in an interview.
 

Study details

The trial, dubbed PRODIGE 13, was done to bring clarity to the surveillance issue. Intensive follow-up after curative surgery for colorectal cancer, including CT and CEA monitoring, is recommended by various scientific societies, but it’s based mainly on expert opinion. Results of the few clinical trials on the issue have been controversial, Dr. Lepage explained.

PRODIGE 13 included 1,995 subjects with colorectal cancer. About half of patients had stage II disease, and the other half had stage III. Most patients were 75 years or younger at baseline, and there were more men in the study than women. All patients underwent resection with curative intent and had no evidence of residual disease 3 months after surgery. Some patients received adjuvant chemotherapy.

Patients were first randomized to no CEA monitoring or CEA monitoring every 3 months for the first 2 years, then every 6 months for an additional 3 years. Members in both groups were then randomized a second time to either intensive or standard radiologic surveillance.

Surveillance in the standard arm consisted of an abdominal ultrasound every 3 months for the first 3 years, then biannually for an additional 2 years, plus chest x-rays every 6 months for 5 years. Intensive surveillance consisted of CT imaging, including thoracic imaging, alternating with abdominal ultrasound, every 3 months, then biannually for another 2 years.

At baseline, the surveillance groups were well balanced with regard to demographics, primary tumor location, and other factors, but stage III disease was more prevalent among patients randomized to standard radiologic monitoring without CEA.
 

Results

The median follow up was 6.5 years. There were no significant differences between the surveillance groups with regard to 5-year overall survival (P = .340) or recurrence-free survival (P = .473).

There were no significant differences in recurrence-free or overall survival when patients were stratified by age, sex, stage, CEA at a cut point of 5 mcg/L, and primary tumor characteristics including location, perineural invasion, and occlusion/perforation.

There were 356 recurrences in patients initially treated for colon cancer. CEA surveillance with or without CT scan was associated with an increased incidence of secondary resection with curative intent. The rate of secondary resection was 66.3% in the standard imaging with CEA arm, 59.5% in the CT plus CEA arm, 50.7% with CT imaging but no CEA, and 40.9% with standard imaging and no CEA (P = .0035).

The rates were similar among the 83 patients with recurrence after initial treatment for rectal cancer, but the between-arm differences were not significant. The rate of secondary resection with curative intent was 57.9% in the standard imaging with CEA arm, 47.8% in the CT plus CEA arm, 55% with CT imaging but no CEA, and 42.9% with standard imaging and no CEA.

The research is ongoing, and the team expects to report on secondary outcomes and ancillary studies of circulating tumor DNA, among other things, in 2021.

The study is being funded by the Federation Francophone de Cancerologie Digestive. Dr. Lepage disclosed ties with Novartis, Amgen, Bayer, Servier, and AAA. Dr. Price disclosed institutional research funding from Amgen and being an uncompensated adviser to Pierre-Fabre and Merck.

[email protected]

SOURCE: Lepage C et al. ESMO 2020, Abstract 398O.

Treating hypertension with angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) was associated with a reduced risk for colorectal cancer, according to findings from a large retrospective study.

However, another study reported just over a year ago suggested that ACE inhibitors, but not ARBs, are associated with an increased risk for lung cancer. An expert approached for comment emphasized that both studies are observational, and, as such, they only show an association, not causation.

In this latest study, published online July 6 in the journal Hypertension, the use of ACE inhibitors/ARBs was associated with a 22% lower risk for colorectal cancer developing within 3 years after a negative baseline colonoscopy.

This is the largest study to date, with a cohort of more than 185,000 patients, to suggest a significant protective effect for these two common antihypertensive medications, the authors note. The risk of developing colorectal cancer decreased with longer duration of ACE inhibitor/ARB use, with a 5% reduction in adjusted hazard ratio risk for each year of use. However, this effect was limited to patients who had negative colonoscopies within a 3-year period and did not extend beyond that point.

Lead author Wai K. Leung, MD, clinical professor of medicine at the University of Hong Kong, explained that they are not advising patients to take ACE inhibitors simply to prevent cancer. “Unlike aspirin and statins, the potential chemopreventive role of ACE inhibitors on cancer has never been established,” he said in an interview. “The study findings may favor the use of ACE inhibitors in the treatment of hypertension, over many other antihypertensives, in some patients for preventing colorectal cancer.”

Increased or reduced risk?

There has been considerable debate about the potential carcinogenic effects of ACE inhibitors and ARBs, and the relationship with “various solid organ cancer risks have been unsettled,” the authors note. Studies have produced conflicting results – showing no overall cancer risk and a modestly increased overall cancer risk – associated with these agents.

A recent study reported that ACE inhibitors, as compared with ARBs, increased risk for lung cancer by 14%. The risk for lung cancer increased by 22% among those using ACE inhibitors for 5 years, and the risk peaked at 31% for patients who took ACE inhibitors for 10 years or longer.

The lead author of that lung cancer study, Laurent Azoulay, PhD, of McGill University in Montreal, offered some thoughts on the seemingly conflicting data now being reported showing a reduction in the risk of colorectal cancer.

“In a nutshell, this study has important methodologic issues that can explain the observed findings,” he said in an interview.

Dr. Azoulay pointed out that, in the univariate model, the use of ACE inhibitors/ARBs was associated with a 26% increased risk of colorectal cancer. “It is only after propensity score adjustment that the effect estimate reversed in the protective direction,” he pointed out. “However, the variables included in the propensity score model were measured in the same time window as the exposure, which can lead to an overadjustment bias and generate spurious findings.”

Another issue is that the study period did not begin at the time of the exposure, but rather at a distant point after treatment initiation – in this case, colorectal cancer screening. “As such, the authors excluded patients who were previously diagnosed with colorectal cancer prior to that point, which likely included patients exposed to ACE inhibitors/ARBs,” he said. “This approach can lead to the inclusion of the ‘survivors’ for whom the risk of developing colorectal cancer is lower.

“But certainly,” Dr. Azoulay added, “this possible association should be investigated using methodologically sound approaches.”

Take-home message for physicians

Another expert emphasized the observational nature of both studies. Raymond Townsend, MD, director of the Hypertension Program and a professor of medicine at the Hospital of the University of Pennsylvania, Philadelphia, said: “First and foremost, these are observational studies and cannot make inference about causality; they can only show associations.”

He pointed out that, sometimes, associations are truly present, whereas at other times, there is bias or confounding that cannot be controlled for statistically because it is “unknown.” That said, the size of this latest study is a plus, and there is a reasonable follow-up period.

“The take-home [message] for practitioners is that there may be a benefit in keeping older people on ACE inhibitors on the likelihood of developing colorectal cancer if your last colonoscopy was negative,” Dr. Townsend, who was not involved in the study, said in an interview.

But there are some questions that remain unanswered regarding characteristics of the cohort, Dr. Townsend noted. “Who were the people having the colonoscopy in the first place? Were they a group at higher risk? Why were some on an ACE inhibitors/ARBs and many others not?” 

There are other conclusions that clinicians can glean from this. “Make a choice of treatment for a patient based on your best estimate of what will lower their blood pressure and prevent hypertension-mediated organ damage,” said Dr. Townsend, who is also an American Heart Association volunteer expert. “Keep in mind that patients hear about these studies and read unreviewed blogs on the web and so have questions.”

He emphasized that it always comes back to two things. “One is that every treatment decision is inherently a risk-benefit scenario,” he said. “And second is that most of our patients are adults, and if they choose to not be treated for their hypertension despite our best advice and reasoning with them, relinquish control and let them proceed as they wish, offering to renegotiate in the future when and if they reconsider.”

Study details

In the latest study, Dr. Leung and colleagues conducted a retrospective cohort study and used data from an electronic health care database of the Hong Kong Hospital Authority. A total of 187,897 individuals aged 40 years and older had undergone colonoscopy between 2005 and 2013 with a negative result and were included in the analysis.

The study’s primary outcome was colorectal cancer that was diagnosed between 6 and 36 months after undergoing colonoscopy, and the median age at colonoscopy was 60.6 years. Within this population, 30,856 patients (16.4%) used ACE inhibitors/ARBs.

Between 6 months and 3 years after undergoing colonoscopy, 854 cases of colorectal cancer were diagnosed, with an incidence rate of 15.2 per 10,000 person-years. The median time between colonoscopy and diagnosis was 1.2 years.

ACE inhibitor/ARB users had a median duration of 3.3 years of use within the 5-year period before their colonoscopy. Within this group, there were 169 (0.55%) cases of colorectal cancer. On univariate analysis, the crude hazard ratio (HR) of colorectal cancer and ACE inhibitor/ARB use was 1.26 (P = .008), but on propensity score regression adjustment, the adjusted HR became 0.78.

The propensity score absolute reduction in risk for users was 3.2 per 10,000 person-years versus nonusers, and stratification by subsite showed an HR of 0.77 for distal cancers and 0.83 for proximal cancers.

In a subgroup analysis, the benefits of ACE inhibitors and ARBs were seen in patients aged 55 years or older (adjusted HR, 0.79) and in those with a history of colonic polyps (adjusted HR, 0.71).

The authors also assessed if there was an association between these medications and other types of cancer. On univariate analysis, usage was associated with an increased risk of lung and prostate cancer but lower risk of breast cancer. But after propensity score regression adjustment, the associations were no longer there.

The study was funded by the Health and Medical Research Fund of the Hong Kong SAR Government. Dr. Leung has received honorarium for attending advisory board meetings of AbbVie, Takeda, and Abbott Laboratories; coauthor Esther W. Chan has received funding support from Pfizer, Bristol-Myers Squibb, Bayer, Takeda, Janssen (a division of Johnson & Johnson); Research Grants Council of Hong Kong; Narcotics Division, Security Bureau; and the National Natural Science Foundation of China, all for work unrelated to the current study. None of the other authors have disclosed relevant financial relationships. Dr. Azoulay has disclosed no relevant financial relationships. Dr. Townsend is employed by Penn Medicine.

A version of this article originally appeared on Medscape.com.

Treating hypertension with angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) was associated with a reduced risk for colorectal cancer, according to findings from a large retrospective study.

However, another study reported just over a year ago suggested that ACE inhibitors, but not ARBs, are associated with an increased risk for lung cancer. An expert approached for comment emphasized that both studies are observational, and, as such, they only show an association, not causation.

In this latest study, published online July 6 in the journal Hypertension, the use of ACE inhibitors/ARBs was associated with a 22% lower risk for colorectal cancer developing within 3 years after a negative baseline colonoscopy.

This is the largest study to date, with a cohort of more than 185,000 patients, to suggest a significant protective effect for these two common antihypertensive medications, the authors note. The risk of developing colorectal cancer decreased with longer duration of ACE inhibitor/ARB use, with a 5% reduction in adjusted hazard ratio risk for each year of use. However, this effect was limited to patients who had negative colonoscopies within a 3-year period and did not extend beyond that point.

Lead author Wai K. Leung, MD, clinical professor of medicine at the University of Hong Kong, explained that they are not advising patients to take ACE inhibitors simply to prevent cancer. “Unlike aspirin and statins, the potential chemopreventive role of ACE inhibitors on cancer has never been established,” he said in an interview. “The study findings may favor the use of ACE inhibitors in the treatment of hypertension, over many other antihypertensives, in some patients for preventing colorectal cancer.”

Increased or reduced risk?

There has been considerable debate about the potential carcinogenic effects of ACE inhibitors and ARBs, and the relationship with “various solid organ cancer risks have been unsettled,” the authors note. Studies have produced conflicting results – showing no overall cancer risk and a modestly increased overall cancer risk – associated with these agents.

A recent study reported that ACE inhibitors, as compared with ARBs, increased risk for lung cancer by 14%. The risk for lung cancer increased by 22% among those using ACE inhibitors for 5 years, and the risk peaked at 31% for patients who took ACE inhibitors for 10 years or longer.

The lead author of that lung cancer study, Laurent Azoulay, PhD, of McGill University in Montreal, offered some thoughts on the seemingly conflicting data now being reported showing a reduction in the risk of colorectal cancer.

“In a nutshell, this study has important methodologic issues that can explain the observed findings,” he said in an interview.

Dr. Azoulay pointed out that, in the univariate model, the use of ACE inhibitors/ARBs was associated with a 26% increased risk of colorectal cancer. “It is only after propensity score adjustment that the effect estimate reversed in the protective direction,” he pointed out. “However, the variables included in the propensity score model were measured in the same time window as the exposure, which can lead to an overadjustment bias and generate spurious findings.”

Another issue is that the study period did not begin at the time of the exposure, but rather at a distant point after treatment initiation – in this case, colorectal cancer screening. “As such, the authors excluded patients who were previously diagnosed with colorectal cancer prior to that point, which likely included patients exposed to ACE inhibitors/ARBs,” he said. “This approach can lead to the inclusion of the ‘survivors’ for whom the risk of developing colorectal cancer is lower.

“But certainly,” Dr. Azoulay added, “this possible association should be investigated using methodologically sound approaches.”

Take-home message for physicians

Another expert emphasized the observational nature of both studies. Raymond Townsend, MD, director of the Hypertension Program and a professor of medicine at the Hospital of the University of Pennsylvania, Philadelphia, said: “First and foremost, these are observational studies and cannot make inference about causality; they can only show associations.”

He pointed out that, sometimes, associations are truly present, whereas at other times, there is bias or confounding that cannot be controlled for statistically because it is “unknown.” That said, the size of this latest study is a plus, and there is a reasonable follow-up period.

“The take-home [message] for practitioners is that there may be a benefit in keeping older people on ACE inhibitors on the likelihood of developing colorectal cancer if your last colonoscopy was negative,” Dr. Townsend, who was not involved in the study, said in an interview.

But there are some questions that remain unanswered regarding characteristics of the cohort, Dr. Townsend noted. “Who were the people having the colonoscopy in the first place? Were they a group at higher risk? Why were some on an ACE inhibitors/ARBs and many others not?” 

There are other conclusions that clinicians can glean from this. “Make a choice of treatment for a patient based on your best estimate of what will lower their blood pressure and prevent hypertension-mediated organ damage,” said Dr. Townsend, who is also an American Heart Association volunteer expert. “Keep in mind that patients hear about these studies and read unreviewed blogs on the web and so have questions.”

He emphasized that it always comes back to two things. “One is that every treatment decision is inherently a risk-benefit scenario,” he said. “And second is that most of our patients are adults, and if they choose to not be treated for their hypertension despite our best advice and reasoning with them, relinquish control and let them proceed as they wish, offering to renegotiate in the future when and if they reconsider.”

Study details

In the latest study, Dr. Leung and colleagues conducted a retrospective cohort study and used data from an electronic health care database of the Hong Kong Hospital Authority. A total of 187,897 individuals aged 40 years and older had undergone colonoscopy between 2005 and 2013 with a negative result and were included in the analysis.

The study’s primary outcome was colorectal cancer that was diagnosed between 6 and 36 months after undergoing colonoscopy, and the median age at colonoscopy was 60.6 years. Within this population, 30,856 patients (16.4%) used ACE inhibitors/ARBs.

Between 6 months and 3 years after undergoing colonoscopy, 854 cases of colorectal cancer were diagnosed, with an incidence rate of 15.2 per 10,000 person-years. The median time between colonoscopy and diagnosis was 1.2 years.

ACE inhibitor/ARB users had a median duration of 3.3 years of use within the 5-year period before their colonoscopy. Within this group, there were 169 (0.55%) cases of colorectal cancer. On univariate analysis, the crude hazard ratio (HR) of colorectal cancer and ACE inhibitor/ARB use was 1.26 (P = .008), but on propensity score regression adjustment, the adjusted HR became 0.78.

The propensity score absolute reduction in risk for users was 3.2 per 10,000 person-years versus nonusers, and stratification by subsite showed an HR of 0.77 for distal cancers and 0.83 for proximal cancers.

In a subgroup analysis, the benefits of ACE inhibitors and ARBs were seen in patients aged 55 years or older (adjusted HR, 0.79) and in those with a history of colonic polyps (adjusted HR, 0.71).

The authors also assessed if there was an association between these medications and other types of cancer. On univariate analysis, usage was associated with an increased risk of lung and prostate cancer but lower risk of breast cancer. But after propensity score regression adjustment, the associations were no longer there.

The study was funded by the Health and Medical Research Fund of the Hong Kong SAR Government. Dr. Leung has received honorarium for attending advisory board meetings of AbbVie, Takeda, and Abbott Laboratories; coauthor Esther W. Chan has received funding support from Pfizer, Bristol-Myers Squibb, Bayer, Takeda, Janssen (a division of Johnson & Johnson); Research Grants Council of Hong Kong; Narcotics Division, Security Bureau; and the National Natural Science Foundation of China, all for work unrelated to the current study. None of the other authors have disclosed relevant financial relationships. Dr. Azoulay has disclosed no relevant financial relationships. Dr. Townsend is employed by Penn Medicine.

A version of this article originally appeared on Medscape.com.

Treating hypertension with angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) was associated with a reduced risk for colorectal cancer, according to findings from a large retrospective study.

However, another study reported just over a year ago suggested that ACE inhibitors, but not ARBs, are associated with an increased risk for lung cancer. An expert approached for comment emphasized that both studies are observational, and, as such, they only show an association, not causation.

In this latest study, published online July 6 in the journal Hypertension, the use of ACE inhibitors/ARBs was associated with a 22% lower risk for colorectal cancer developing within 3 years after a negative baseline colonoscopy.

This is the largest study to date, with a cohort of more than 185,000 patients, to suggest a significant protective effect for these two common antihypertensive medications, the authors note. The risk of developing colorectal cancer decreased with longer duration of ACE inhibitor/ARB use, with a 5% reduction in adjusted hazard ratio risk for each year of use. However, this effect was limited to patients who had negative colonoscopies within a 3-year period and did not extend beyond that point.

Lead author Wai K. Leung, MD, clinical professor of medicine at the University of Hong Kong, explained that they are not advising patients to take ACE inhibitors simply to prevent cancer. “Unlike aspirin and statins, the potential chemopreventive role of ACE inhibitors on cancer has never been established,” he said in an interview. “The study findings may favor the use of ACE inhibitors in the treatment of hypertension, over many other antihypertensives, in some patients for preventing colorectal cancer.”

Increased or reduced risk?

There has been considerable debate about the potential carcinogenic effects of ACE inhibitors and ARBs, and the relationship with “various solid organ cancer risks have been unsettled,” the authors note. Studies have produced conflicting results – showing no overall cancer risk and a modestly increased overall cancer risk – associated with these agents.

A recent study reported that ACE inhibitors, as compared with ARBs, increased risk for lung cancer by 14%. The risk for lung cancer increased by 22% among those using ACE inhibitors for 5 years, and the risk peaked at 31% for patients who took ACE inhibitors for 10 years or longer.

The lead author of that lung cancer study, Laurent Azoulay, PhD, of McGill University in Montreal, offered some thoughts on the seemingly conflicting data now being reported showing a reduction in the risk of colorectal cancer.

“In a nutshell, this study has important methodologic issues that can explain the observed findings,” he said in an interview.

Dr. Azoulay pointed out that, in the univariate model, the use of ACE inhibitors/ARBs was associated with a 26% increased risk of colorectal cancer. “It is only after propensity score adjustment that the effect estimate reversed in the protective direction,” he pointed out. “However, the variables included in the propensity score model were measured in the same time window as the exposure, which can lead to an overadjustment bias and generate spurious findings.”

Another issue is that the study period did not begin at the time of the exposure, but rather at a distant point after treatment initiation – in this case, colorectal cancer screening. “As such, the authors excluded patients who were previously diagnosed with colorectal cancer prior to that point, which likely included patients exposed to ACE inhibitors/ARBs,” he said. “This approach can lead to the inclusion of the ‘survivors’ for whom the risk of developing colorectal cancer is lower.

“But certainly,” Dr. Azoulay added, “this possible association should be investigated using methodologically sound approaches.”

Take-home message for physicians

Another expert emphasized the observational nature of both studies. Raymond Townsend, MD, director of the Hypertension Program and a professor of medicine at the Hospital of the University of Pennsylvania, Philadelphia, said: “First and foremost, these are observational studies and cannot make inference about causality; they can only show associations.”

He pointed out that, sometimes, associations are truly present, whereas at other times, there is bias or confounding that cannot be controlled for statistically because it is “unknown.” That said, the size of this latest study is a plus, and there is a reasonable follow-up period.

“The take-home [message] for practitioners is that there may be a benefit in keeping older people on ACE inhibitors on the likelihood of developing colorectal cancer if your last colonoscopy was negative,” Dr. Townsend, who was not involved in the study, said in an interview.

But there are some questions that remain unanswered regarding characteristics of the cohort, Dr. Townsend noted. “Who were the people having the colonoscopy in the first place? Were they a group at higher risk? Why were some on an ACE inhibitors/ARBs and many others not?” 

There are other conclusions that clinicians can glean from this. “Make a choice of treatment for a patient based on your best estimate of what will lower their blood pressure and prevent hypertension-mediated organ damage,” said Dr. Townsend, who is also an American Heart Association volunteer expert. “Keep in mind that patients hear about these studies and read unreviewed blogs on the web and so have questions.”

He emphasized that it always comes back to two things. “One is that every treatment decision is inherently a risk-benefit scenario,” he said. “And second is that most of our patients are adults, and if they choose to not be treated for their hypertension despite our best advice and reasoning with them, relinquish control and let them proceed as they wish, offering to renegotiate in the future when and if they reconsider.”

Study details

In the latest study, Dr. Leung and colleagues conducted a retrospective cohort study and used data from an electronic health care database of the Hong Kong Hospital Authority. A total of 187,897 individuals aged 40 years and older had undergone colonoscopy between 2005 and 2013 with a negative result and were included in the analysis.

The study’s primary outcome was colorectal cancer that was diagnosed between 6 and 36 months after undergoing colonoscopy, and the median age at colonoscopy was 60.6 years. Within this population, 30,856 patients (16.4%) used ACE inhibitors/ARBs.

Between 6 months and 3 years after undergoing colonoscopy, 854 cases of colorectal cancer were diagnosed, with an incidence rate of 15.2 per 10,000 person-years. The median time between colonoscopy and diagnosis was 1.2 years.

ACE inhibitor/ARB users had a median duration of 3.3 years of use within the 5-year period before their colonoscopy. Within this group, there were 169 (0.55%) cases of colorectal cancer. On univariate analysis, the crude hazard ratio (HR) of colorectal cancer and ACE inhibitor/ARB use was 1.26 (P = .008), but on propensity score regression adjustment, the adjusted HR became 0.78.

The propensity score absolute reduction in risk for users was 3.2 per 10,000 person-years versus nonusers, and stratification by subsite showed an HR of 0.77 for distal cancers and 0.83 for proximal cancers.

In a subgroup analysis, the benefits of ACE inhibitors and ARBs were seen in patients aged 55 years or older (adjusted HR, 0.79) and in those with a history of colonic polyps (adjusted HR, 0.71).

The authors also assessed if there was an association between these medications and other types of cancer. On univariate analysis, usage was associated with an increased risk of lung and prostate cancer but lower risk of breast cancer. But after propensity score regression adjustment, the associations were no longer there.

The study was funded by the Health and Medical Research Fund of the Hong Kong SAR Government. Dr. Leung has received honorarium for attending advisory board meetings of AbbVie, Takeda, and Abbott Laboratories; coauthor Esther W. Chan has received funding support from Pfizer, Bristol-Myers Squibb, Bayer, Takeda, Janssen (a division of Johnson & Johnson); Research Grants Council of Hong Kong; Narcotics Division, Security Bureau; and the National Natural Science Foundation of China, all for work unrelated to the current study. None of the other authors have disclosed relevant financial relationships. Dr. Azoulay has disclosed no relevant financial relationships. Dr. Townsend is employed by Penn Medicine.

A version of this article originally appeared on Medscape.com.