Informed choice is important, from making health care decisions to deciding on which neighbourhood to live in, what university to choose and more. We all make decisions based on information to help understand the pros and cons of a potential action. Information is especially important when it comes to health decisions as many Canadians do not have access to a regular health care provider.
Access to quality information on the benefits and risks of a health choice is essential in medicine. When considering surgery, doctors give patients information on the benefits and harms of a procedure so that they can decide what is best for themselves. Women experiencing menopause may consider hormone replacement therapy. What are the benefits and potential harms? Is it right for me? These are personal decisions made with the help of credible information and a conversation with a health care provider.
That is the underlying principle of the draft recommendations on breast cancer screening released earlier this year by the Canadian Task Force on Preventive Health Care (Task Force): breast cancer screening is a personal choice, and women need information on the benefits and harms so that they can decide what is right for them.
Breast cancer is a terrible disease and we all want to find ways to lessen its impact and improve outcomes. That’s why the family physicians, nurse practitioners, researchers and specialists on the Task Force conducted a comprehensive review of evidence on breast cancer screening in women aged 40-74. This review included more than 155 studies, with recent observational trials, randomized controlled trials and modelling informing the draft recommendations released May 30, 3024.
Surprisingly, the evidence did not show a clear benefit of screening in women aged 40-49.
As part of the evidence review, the Task Force conducted a systematic review of patient values and preferences for breast cancer screening which showed that a majority of patients aged 40-49 might not think the benefits outweigh the harms.
“We all want to find ways to reduce the burden of breast cancer and improve outcomes,” said Dr. Guylène Thériault, a family physician, teacher of evidence-based medicine and chair of the Task Force and the breast cancer working group. “People may find that information about breast cancer screening is surprising – there are potential benefits to screening, but there are also harms. We want women to have all the information they need to make the decision that’s right for them.”
Who are the recommendations for?
The recommendations are for women at average or moderately increased risk, that is, those with dense breast category C or D or moderate family history (no more than one first degree or two second degree relatives diagnosed after 50). The recommendations do not apply to those with a personal or extensive family history of breast cancer or genetic mutations that would increase breast cancer risk. They also do not apply to people with symptoms, such as a lump, those who feel they may be at high risk, and transgender women. These individuals should consult a healthcare provider about appropriate options.
Lack of evidence for key groups
The Task Force found that there is a lack of evidence on screening in Black women and other diverse races/ethnicities, and in those with dense breasts. That’s why they are calling for more evidence to better understand breast cancer in these populations and the best ways to reduce the burden of disease and deaths.
Breast cancer experts and patient involvement
The breast cancer guideline working group included 4 breast cancer content experts - a medical oncologist, radiation oncologist, surgical oncologist and radiologist - to ensure a comprehensive look at each step. As the patient perspective is essential in guideline development, three diverse patient partners (two with lived experience of breast cancer) provided valuable input as members of the working group.
As we move into breast cancer awareness month, it’s important to be clear. The key message of the draft guideline is that people aged 40 to 74 should be provided information about the benefits and harms of breast cancer screening to make a decision that aligns with their values and preferences. This is a principle consistent with current healthcare practices. If, after being informed, a woman wants to be screened, she should be offered a mammogram every 2-3 years.
The draft recommendations, evidence reviews and age-based decision tools for patients can be found here.
The final guideline will be published in 2025, with feedback on the draft summarized and posted online.
Dr. Guylène Thériault, Chair, Canadian Task Force on Preventive Health Care
Dr. Donna L. Reynolds, Family Physician, Assistant Professor and Public Health and Preventive Medicine Specialist