Article Type
Changed
Wed, 07/10/2024 - 12:09

Potential harms and benefits should be weighed carefully before women and their physicians decide on breast cancer screening, according to updated guidelines from the Canadian Task Force on Preventive Health Care.

The draft guidelines stem from a review of more than 165 recent randomized controlled trials, observational studies, mathematical models, and other data.

The guideline working group included four breast cancer experts (a medical oncologist, a radiation oncologist, a surgical oncologist, and a radiologist), three patient partners, six family physicians, a nurse practitioner, evidence review teams, and other experts.

To avoid potential conflicts of interest, the oncologists provided input but did not vote on the final recommendations, Guylène Thériault, MD, a family physician and chair of the task force and Breast Cancer Working Group, said in an interview. 

The guideline recommends that, after the potential benefits and harms of screening have been considered, mammography should be accessible every 2-3 years to women (ie, people assigned female at birth) between ages 40 and 74 years who are at average or moderately increased risk.

Women with a personal or extensive family history of breast cancer or genetic mutations that would increase breast cancer risk; those who have symptoms, such as a lump; those who feel they may be at high risk; and those who are transgender women should consult a healthcare provider about appropriate options, according to the updated guidelines, which do not apply to these patients.

The draft guidelines were published online on May 30 and are open for public comment until August 30.
 

‘Three Big Questions’

To develop the guidelines, the work group asked “three big questions,” said Dr. Thériault. The first was the effectiveness of breast cancer screening for women aged 40 years and over. For this question, this systematic review, unlike the 2018 guideline update, included not only randomized trials but also observational data to ensure that the work group considered all available data.

“The second question was about comparative effectiveness,” which is something the United States considered for the latest US Preventive Services Task Force (USPSTF) update, said Dr. Thériault. The USPSTF asked questions such as “What happens if we start screening patients at age 40 years? Or at age 50 years? What happens if we stop at age 74 years? Or if we use different tests such as 3D versus digital mammography?”

The Canadian Task Force relied on the evidence that the USPSTF found after grading it with its own criteria, she said. The results were similar, and so are the recommendations in this area. “For example, we don’t recommend supplementary screening for women with dense breasts because there are no studies to inform patient-oriented benefits.”

The third question was about the values and preferences of women regarding breast cancer screening, which is something the United States didn’t examine. “We had looked at that issue in 2018, and this time around, even though we expanded the type of studies, we got the same message: That there are differences between women in their 40s and those who are age 50 years and over.”

“The majority of women in their 40s think that the harms outweigh the benefits and are not interested in screening,” said Dr. Thériault. “But when I say the majority, that’s not every woman. So, we had to recognize that there is variability. And the majority, but not all, of women ages 50-74 years thinks the benefits are higher than the harms. That’s why we say in our recommendation that from ages 40 to 74, it’s a personal choice.”
 

 

 

Responding to Objections

Not surprisingly, the task force has heard objections to its draft guidelines. The first is that women aged 40-49 years are being denied mammograms, said Michelle Nadler, MD, a medical oncologist at Princess Margaret Cancer Centre in Toronto, Canada. “This [objection] has attained a lot of media coverage, which is unfortunate, because people who have not read the guidelines may believe this is true. The guidelines clearly state that an eligible, informed woman of this age group who wants a screening mammogram should receive one.”

The second commonly heard objection is that the task force is overestimating the harms of screening, such as anxiety and overdiagnosis, she said. But an outcome of “anxiety” was not factored into the guideline. Overdiagnosis was calculated on the basis of the literature, and estimates were converted to a common denominator so that they could be compared, said Dr. Nadler. The same was true of benefits.

Another objection was that screening could mean less need for chemotherapy or full axillary dissection, Dr. Nadler said. However, the task force did not find any primary studies that evaluated these outcomes.

Critics also said that the recommendations do not account for racial or ethnic variations. Although more research is likely needed in this area, “the task force states that individuals should be informed of all of their breast cancer risk factors, including race/ethnicity, and that this should be factored into decisions about screening,” said Dr. Nadler.

“I was very surprised that the task force was accused by some parties of paternalism,” added René Wittmer, MD, adjunct clinical professor of family medicine at the University of Montreal and chair of Choosing Wisely Quebec, Montreal, Canada. “In my opinion, the importance they place on shared decision-making is contrary to medical paternalism and aims to empower women to make a decision that fits with their values and preferences.”

Nevertheless, the inclusion of modeling studies and observational trials “may cause the potential benefits to be amplified, compared with what is seen in randomized controlled trials,” he said in an interview.
 

Decision Aids Help

Once the guidelines are finalized, decision aids will be available to patients and providers to help guide screening discussions, said Dr. Nadler. “Primary care providers need to be aware of an individual’s personal risk factors for breast cancer to know if they are at average, above average, or high lifetime risk of breast cancer. These guidelines do not apply to those with > 20% lifetime risk of breast cancer.”

“The standards for risk communication are in absolute numbers over a common denominator,” she noted. “This is how primary care providers discuss other important primary care topics like smoking cessation, cardiovascular disease (and decisions about statin medications), and osteoporosis risk. These same standards should apply for breast cancer screening.”

Furthermore, she said, providers “should be aware that individuals from marginalized communities may benefit from more than one conversation until they are able to make a decision about screening that is right for them.”

“There is good evidence showing that most advances we’ve seen in breast cancer outcomes (ie, reduction in breast cancer mortality) are likely due to improvements in treatment, not screening,” said Dr. Wittmer. “In fact, mortality reductions are seen even in age groups or countries where there is no routine screening. This means that women benefit from advances in treatments, whether they choose to get screened or not.”
 

 

 

‘Mammography Saves Lives’

Commenting on the updated guidelines, Janie Lee, MD, professor of radiology at the University of Washington School of Medicine and director of breast imaging at the Fred Hutchinson Cancer Center, both in Seattle, said: “For the USPSTF, benefits of life years gained were also considered, in addition to breast cancer deaths averted. To save more lives from breast cancer, guidelines may focus on screening women at older ages, when annual rates of breast cancer are higher.” By contrast, when thinking in terms of years of life saved, focusing on screening younger women, who have more years of life left, increases benefits. “Both are important outcomes that we want to improve with effective screening.”

That said, “we should follow the guidelines of our specific national organizations,” she continued. “Overall populations and healthcare systems are different between the US and Canada.”

For example, “the USPSTF specifically highlighted the potential for reducing breast cancer mortality in Black women, who are more likely to develop biologically aggressive tumors that are diagnosed at more advanced stages, when making updated recommendations earlier this year,” she said. “The Canadian guidelines did not make specific recommendations by race or ethnicity group, instead highlighting the need for more research on the impact of screening in these groups.”

In addition, “screening every year versus every other year is more routine in the US compared with Canada,” she noted. And nonmedical factors that influence health and that may influence access to medical care and timely diagnosis of breast cancer “may be different between our two countries.”

“The most important take-home message is that the scientific evidence is strong that screening mammography saves lives,” said Dr. Lee. “These new recommendations will hopefully result in more early diagnoses of breast cancer and save more lives. Screening works best when it’s used regularly, regardless of how frequently you return. Once you start screening, please urge your patients to plan to return.”

Dr. Nadler disclosed speaker honoraria and consulting fees from Novartis and Exact Sciences outside the scope of this interview and innovation funding from the NSH/UHN AMO Innovation Fund Competition for Developing and Implementing a Consensus Recommendation for Breast Cancer Screening Best Practices. Dr. Thériault is chair of the task force and chair of the working group for the draft guidelines. Dr. Wittmer is chair of Choosing Wisely Quebec. Dr. Lee reported no relevant financial relationships related to her interview.

A version of this article appeared on Medscape.com.

Publications
Topics
Sections

Potential harms and benefits should be weighed carefully before women and their physicians decide on breast cancer screening, according to updated guidelines from the Canadian Task Force on Preventive Health Care.

The draft guidelines stem from a review of more than 165 recent randomized controlled trials, observational studies, mathematical models, and other data.

The guideline working group included four breast cancer experts (a medical oncologist, a radiation oncologist, a surgical oncologist, and a radiologist), three patient partners, six family physicians, a nurse practitioner, evidence review teams, and other experts.

To avoid potential conflicts of interest, the oncologists provided input but did not vote on the final recommendations, Guylène Thériault, MD, a family physician and chair of the task force and Breast Cancer Working Group, said in an interview. 

The guideline recommends that, after the potential benefits and harms of screening have been considered, mammography should be accessible every 2-3 years to women (ie, people assigned female at birth) between ages 40 and 74 years who are at average or moderately increased risk.

Women with a personal or extensive family history of breast cancer or genetic mutations that would increase breast cancer risk; those who have symptoms, such as a lump; those who feel they may be at high risk; and those who are transgender women should consult a healthcare provider about appropriate options, according to the updated guidelines, which do not apply to these patients.

The draft guidelines were published online on May 30 and are open for public comment until August 30.
 

‘Three Big Questions’

To develop the guidelines, the work group asked “three big questions,” said Dr. Thériault. The first was the effectiveness of breast cancer screening for women aged 40 years and over. For this question, this systematic review, unlike the 2018 guideline update, included not only randomized trials but also observational data to ensure that the work group considered all available data.

“The second question was about comparative effectiveness,” which is something the United States considered for the latest US Preventive Services Task Force (USPSTF) update, said Dr. Thériault. The USPSTF asked questions such as “What happens if we start screening patients at age 40 years? Or at age 50 years? What happens if we stop at age 74 years? Or if we use different tests such as 3D versus digital mammography?”

The Canadian Task Force relied on the evidence that the USPSTF found after grading it with its own criteria, she said. The results were similar, and so are the recommendations in this area. “For example, we don’t recommend supplementary screening for women with dense breasts because there are no studies to inform patient-oriented benefits.”

The third question was about the values and preferences of women regarding breast cancer screening, which is something the United States didn’t examine. “We had looked at that issue in 2018, and this time around, even though we expanded the type of studies, we got the same message: That there are differences between women in their 40s and those who are age 50 years and over.”

“The majority of women in their 40s think that the harms outweigh the benefits and are not interested in screening,” said Dr. Thériault. “But when I say the majority, that’s not every woman. So, we had to recognize that there is variability. And the majority, but not all, of women ages 50-74 years thinks the benefits are higher than the harms. That’s why we say in our recommendation that from ages 40 to 74, it’s a personal choice.”
 

 

 

Responding to Objections

Not surprisingly, the task force has heard objections to its draft guidelines. The first is that women aged 40-49 years are being denied mammograms, said Michelle Nadler, MD, a medical oncologist at Princess Margaret Cancer Centre in Toronto, Canada. “This [objection] has attained a lot of media coverage, which is unfortunate, because people who have not read the guidelines may believe this is true. The guidelines clearly state that an eligible, informed woman of this age group who wants a screening mammogram should receive one.”

The second commonly heard objection is that the task force is overestimating the harms of screening, such as anxiety and overdiagnosis, she said. But an outcome of “anxiety” was not factored into the guideline. Overdiagnosis was calculated on the basis of the literature, and estimates were converted to a common denominator so that they could be compared, said Dr. Nadler. The same was true of benefits.

Another objection was that screening could mean less need for chemotherapy or full axillary dissection, Dr. Nadler said. However, the task force did not find any primary studies that evaluated these outcomes.

Critics also said that the recommendations do not account for racial or ethnic variations. Although more research is likely needed in this area, “the task force states that individuals should be informed of all of their breast cancer risk factors, including race/ethnicity, and that this should be factored into decisions about screening,” said Dr. Nadler.

“I was very surprised that the task force was accused by some parties of paternalism,” added René Wittmer, MD, adjunct clinical professor of family medicine at the University of Montreal and chair of Choosing Wisely Quebec, Montreal, Canada. “In my opinion, the importance they place on shared decision-making is contrary to medical paternalism and aims to empower women to make a decision that fits with their values and preferences.”

Nevertheless, the inclusion of modeling studies and observational trials “may cause the potential benefits to be amplified, compared with what is seen in randomized controlled trials,” he said in an interview.
 

Decision Aids Help

Once the guidelines are finalized, decision aids will be available to patients and providers to help guide screening discussions, said Dr. Nadler. “Primary care providers need to be aware of an individual’s personal risk factors for breast cancer to know if they are at average, above average, or high lifetime risk of breast cancer. These guidelines do not apply to those with > 20% lifetime risk of breast cancer.”

“The standards for risk communication are in absolute numbers over a common denominator,” she noted. “This is how primary care providers discuss other important primary care topics like smoking cessation, cardiovascular disease (and decisions about statin medications), and osteoporosis risk. These same standards should apply for breast cancer screening.”

Furthermore, she said, providers “should be aware that individuals from marginalized communities may benefit from more than one conversation until they are able to make a decision about screening that is right for them.”

“There is good evidence showing that most advances we’ve seen in breast cancer outcomes (ie, reduction in breast cancer mortality) are likely due to improvements in treatment, not screening,” said Dr. Wittmer. “In fact, mortality reductions are seen even in age groups or countries where there is no routine screening. This means that women benefit from advances in treatments, whether they choose to get screened or not.”
 

 

 

‘Mammography Saves Lives’

Commenting on the updated guidelines, Janie Lee, MD, professor of radiology at the University of Washington School of Medicine and director of breast imaging at the Fred Hutchinson Cancer Center, both in Seattle, said: “For the USPSTF, benefits of life years gained were also considered, in addition to breast cancer deaths averted. To save more lives from breast cancer, guidelines may focus on screening women at older ages, when annual rates of breast cancer are higher.” By contrast, when thinking in terms of years of life saved, focusing on screening younger women, who have more years of life left, increases benefits. “Both are important outcomes that we want to improve with effective screening.”

That said, “we should follow the guidelines of our specific national organizations,” she continued. “Overall populations and healthcare systems are different between the US and Canada.”

For example, “the USPSTF specifically highlighted the potential for reducing breast cancer mortality in Black women, who are more likely to develop biologically aggressive tumors that are diagnosed at more advanced stages, when making updated recommendations earlier this year,” she said. “The Canadian guidelines did not make specific recommendations by race or ethnicity group, instead highlighting the need for more research on the impact of screening in these groups.”

In addition, “screening every year versus every other year is more routine in the US compared with Canada,” she noted. And nonmedical factors that influence health and that may influence access to medical care and timely diagnosis of breast cancer “may be different between our two countries.”

“The most important take-home message is that the scientific evidence is strong that screening mammography saves lives,” said Dr. Lee. “These new recommendations will hopefully result in more early diagnoses of breast cancer and save more lives. Screening works best when it’s used regularly, regardless of how frequently you return. Once you start screening, please urge your patients to plan to return.”

Dr. Nadler disclosed speaker honoraria and consulting fees from Novartis and Exact Sciences outside the scope of this interview and innovation funding from the NSH/UHN AMO Innovation Fund Competition for Developing and Implementing a Consensus Recommendation for Breast Cancer Screening Best Practices. Dr. Thériault is chair of the task force and chair of the working group for the draft guidelines. Dr. Wittmer is chair of Choosing Wisely Quebec. Dr. Lee reported no relevant financial relationships related to her interview.

A version of this article appeared on Medscape.com.

Potential harms and benefits should be weighed carefully before women and their physicians decide on breast cancer screening, according to updated guidelines from the Canadian Task Force on Preventive Health Care.

The draft guidelines stem from a review of more than 165 recent randomized controlled trials, observational studies, mathematical models, and other data.

The guideline working group included four breast cancer experts (a medical oncologist, a radiation oncologist, a surgical oncologist, and a radiologist), three patient partners, six family physicians, a nurse practitioner, evidence review teams, and other experts.

To avoid potential conflicts of interest, the oncologists provided input but did not vote on the final recommendations, Guylène Thériault, MD, a family physician and chair of the task force and Breast Cancer Working Group, said in an interview. 

The guideline recommends that, after the potential benefits and harms of screening have been considered, mammography should be accessible every 2-3 years to women (ie, people assigned female at birth) between ages 40 and 74 years who are at average or moderately increased risk.

Women with a personal or extensive family history of breast cancer or genetic mutations that would increase breast cancer risk; those who have symptoms, such as a lump; those who feel they may be at high risk; and those who are transgender women should consult a healthcare provider about appropriate options, according to the updated guidelines, which do not apply to these patients.

The draft guidelines were published online on May 30 and are open for public comment until August 30.
 

‘Three Big Questions’

To develop the guidelines, the work group asked “three big questions,” said Dr. Thériault. The first was the effectiveness of breast cancer screening for women aged 40 years and over. For this question, this systematic review, unlike the 2018 guideline update, included not only randomized trials but also observational data to ensure that the work group considered all available data.

“The second question was about comparative effectiveness,” which is something the United States considered for the latest US Preventive Services Task Force (USPSTF) update, said Dr. Thériault. The USPSTF asked questions such as “What happens if we start screening patients at age 40 years? Or at age 50 years? What happens if we stop at age 74 years? Or if we use different tests such as 3D versus digital mammography?”

The Canadian Task Force relied on the evidence that the USPSTF found after grading it with its own criteria, she said. The results were similar, and so are the recommendations in this area. “For example, we don’t recommend supplementary screening for women with dense breasts because there are no studies to inform patient-oriented benefits.”

The third question was about the values and preferences of women regarding breast cancer screening, which is something the United States didn’t examine. “We had looked at that issue in 2018, and this time around, even though we expanded the type of studies, we got the same message: That there are differences between women in their 40s and those who are age 50 years and over.”

“The majority of women in their 40s think that the harms outweigh the benefits and are not interested in screening,” said Dr. Thériault. “But when I say the majority, that’s not every woman. So, we had to recognize that there is variability. And the majority, but not all, of women ages 50-74 years thinks the benefits are higher than the harms. That’s why we say in our recommendation that from ages 40 to 74, it’s a personal choice.”
 

 

 

Responding to Objections

Not surprisingly, the task force has heard objections to its draft guidelines. The first is that women aged 40-49 years are being denied mammograms, said Michelle Nadler, MD, a medical oncologist at Princess Margaret Cancer Centre in Toronto, Canada. “This [objection] has attained a lot of media coverage, which is unfortunate, because people who have not read the guidelines may believe this is true. The guidelines clearly state that an eligible, informed woman of this age group who wants a screening mammogram should receive one.”

The second commonly heard objection is that the task force is overestimating the harms of screening, such as anxiety and overdiagnosis, she said. But an outcome of “anxiety” was not factored into the guideline. Overdiagnosis was calculated on the basis of the literature, and estimates were converted to a common denominator so that they could be compared, said Dr. Nadler. The same was true of benefits.

Another objection was that screening could mean less need for chemotherapy or full axillary dissection, Dr. Nadler said. However, the task force did not find any primary studies that evaluated these outcomes.

Critics also said that the recommendations do not account for racial or ethnic variations. Although more research is likely needed in this area, “the task force states that individuals should be informed of all of their breast cancer risk factors, including race/ethnicity, and that this should be factored into decisions about screening,” said Dr. Nadler.

“I was very surprised that the task force was accused by some parties of paternalism,” added René Wittmer, MD, adjunct clinical professor of family medicine at the University of Montreal and chair of Choosing Wisely Quebec, Montreal, Canada. “In my opinion, the importance they place on shared decision-making is contrary to medical paternalism and aims to empower women to make a decision that fits with their values and preferences.”

Nevertheless, the inclusion of modeling studies and observational trials “may cause the potential benefits to be amplified, compared with what is seen in randomized controlled trials,” he said in an interview.
 

Decision Aids Help

Once the guidelines are finalized, decision aids will be available to patients and providers to help guide screening discussions, said Dr. Nadler. “Primary care providers need to be aware of an individual’s personal risk factors for breast cancer to know if they are at average, above average, or high lifetime risk of breast cancer. These guidelines do not apply to those with > 20% lifetime risk of breast cancer.”

“The standards for risk communication are in absolute numbers over a common denominator,” she noted. “This is how primary care providers discuss other important primary care topics like smoking cessation, cardiovascular disease (and decisions about statin medications), and osteoporosis risk. These same standards should apply for breast cancer screening.”

Furthermore, she said, providers “should be aware that individuals from marginalized communities may benefit from more than one conversation until they are able to make a decision about screening that is right for them.”

“There is good evidence showing that most advances we’ve seen in breast cancer outcomes (ie, reduction in breast cancer mortality) are likely due to improvements in treatment, not screening,” said Dr. Wittmer. “In fact, mortality reductions are seen even in age groups or countries where there is no routine screening. This means that women benefit from advances in treatments, whether they choose to get screened or not.”
 

 

 

‘Mammography Saves Lives’

Commenting on the updated guidelines, Janie Lee, MD, professor of radiology at the University of Washington School of Medicine and director of breast imaging at the Fred Hutchinson Cancer Center, both in Seattle, said: “For the USPSTF, benefits of life years gained were also considered, in addition to breast cancer deaths averted. To save more lives from breast cancer, guidelines may focus on screening women at older ages, when annual rates of breast cancer are higher.” By contrast, when thinking in terms of years of life saved, focusing on screening younger women, who have more years of life left, increases benefits. “Both are important outcomes that we want to improve with effective screening.”

That said, “we should follow the guidelines of our specific national organizations,” she continued. “Overall populations and healthcare systems are different between the US and Canada.”

For example, “the USPSTF specifically highlighted the potential for reducing breast cancer mortality in Black women, who are more likely to develop biologically aggressive tumors that are diagnosed at more advanced stages, when making updated recommendations earlier this year,” she said. “The Canadian guidelines did not make specific recommendations by race or ethnicity group, instead highlighting the need for more research on the impact of screening in these groups.”

In addition, “screening every year versus every other year is more routine in the US compared with Canada,” she noted. And nonmedical factors that influence health and that may influence access to medical care and timely diagnosis of breast cancer “may be different between our two countries.”

“The most important take-home message is that the scientific evidence is strong that screening mammography saves lives,” said Dr. Lee. “These new recommendations will hopefully result in more early diagnoses of breast cancer and save more lives. Screening works best when it’s used regularly, regardless of how frequently you return. Once you start screening, please urge your patients to plan to return.”

Dr. Nadler disclosed speaker honoraria and consulting fees from Novartis and Exact Sciences outside the scope of this interview and innovation funding from the NSH/UHN AMO Innovation Fund Competition for Developing and Implementing a Consensus Recommendation for Breast Cancer Screening Best Practices. Dr. Thériault is chair of the task force and chair of the working group for the draft guidelines. Dr. Wittmer is chair of Choosing Wisely Quebec. Dr. Lee reported no relevant financial relationships related to her interview.

A version of this article appeared on Medscape.com.

Publications
Publications
Topics
Article Type
Sections
Disallow All Ads
Content Gating
No Gating (article Unlocked/Free)
Alternative CME
Disqus Comments
Default
Use ProPublica
Hide sidebar & use full width
render the right sidebar.
Conference Recap Checkbox
Not Conference Recap
Clinical Edge
Display the Slideshow in this Article
Medscape Article
Display survey writer
Reuters content
Disable Inline Native ads
WebMD Article