Ignoring reason and evidence: Why new breast cancer guidelines advising against screening women in their 40s are misguided
Despite rapidly increasing breast cancer rates in young women and mounting evidence supporting the efficacy and cost-effectiveness of screening, the Canadian Preventive Health Care Task Force has recommended against systematic screening in women between the ages of 40 and 49 years.
 |
| Image : Google.com//images.app.goo.gl/926oc2nWYarBAXzV8 |
The Canadian Cancer Society and the United States Preventive Services Task Force have changed their recommendations for breast screening, while most provincial governments in Canada have implemented or committed to breast screening starting at age 40.
However, it appears that the Task Force's decision was a foregone conclusion, as leaders expressed reluctance to change the guidelines before the process even began.
This view was reinforced in a recent publication in Canadian Family Physician in which Task Force members rejected the efficacy of screening and treatment development.
Focuses on potential dangers and old data
The Task Force disproportionately focuses on the potential harms of screening, such as overdiagnosis (a cancer diagnosis that will never cause problems for a person in their lifetime) and anxiety about imaging callbacks, while at the same time minimizing the undeniable benefits of saving lives. and reducing suffering through early detection.
Although randomized controlled trials (RCTs) are the gold standard in guideline formulation, the Task Force's reliance on outdated RCTs that are 30 to 60 years old fails to take into account modern diagnostic and treatment advances. The guideline-making process was paused in the fall, with experts demanding that only post-2000 evidence be considered. However, this advice was ignored, and the Task Force continued to disproportionately prioritize older RCTs and underestimate newer observational trials, which are more aligned with current screening and treatment norms.
This reduces the perceived benefit of screening, as the mortality benefit of screening in RCTs was 15 percent, compared with 53 percent in observational trials. The Task Force also only tells part of the benefits of screening by framing the benefits in a limited time span (10 years from the start of screening), and does not realize the benefits obtained throughout a person's life.
Additionally, the Task Force's approach to risk assessment is very simplistic and ignores individual factors, such as race and ethnicity, breast density, and family history. This significantly influences the risk of breast cancer.
But by implementing a uniform model, they risk misinforming women about their risks and denying them access to potentially life-saving tests, especially for women of a race that is significantly more likely to be diagnosed in their 40s.
Perhaps most concerning is the Task Force's contention that many cancers identified through screening will not progress or will regress naturally, leading to unnecessary treatment or “overdiagnosis.” This false reasoning ignores the reality that untreated cancer will inevitably progress, and ignores medical innovations such as genomic recurrence risk profiling that allow for de-escalation of treatment, and minimize overtreatment.
Delaying screening based on the unproven theory that cancer will never cause a problem, when screening provides clear mortality benefits, is unjustified.
Access to care
The Task Force organizes all of its recommendations into “shared decision making,” which urges patients and primary care providers to collaborate to determine what is right for each patient.
In theory, this concept is awesome. However, family physicians rely on the Task Force for guidance on how to counsel their patients, and when they receive inaccurate information about the harms and benefits of screening, the power imbalance between providers and patients undermines the shared and informed nature of decision making. As a result, women's access to important health care options is limited, leading to disparities in breast cancer outcomes.
If the adverse effects of treatment a person faces are not convincing enough, there are financial costs to delaying a breast cancer diagnosis. Research conducted by researchers in Ottawa shows that the cost of treating breast cancer in Ontario varies greatly based on the stage of diagnosis. From $14,505 for ductal carcinoma in situ (DCIS, very early stage breast cancer), to medians of $39,263, $76,446, $97,668 and $370,398 for Stages I, II, III and IV respectively. In a single-payer public health care system, these costs are much greater than the cost of a mammography screening.
The updated Task Force guidelines have used existing science to minimize the benefits of screening and magnify its harms, ultimately preventing women from accessing screening. We believe the consequences of these new guidelines could be dire, with many young women paying the cost of their lives.
The majority of provinces and territories have acknowledged this shortcoming, waived existing guidance, and permitted self-referral for screening for women 40-49, understanding that “shared decision making” creates barriers for women to access screening, especially in this era. unequal access to primary health services.
How is it that the Canadian Cancer Society, the United States, and nine Canadian provinces support screening in women aged 40-49 years, but our national guidelines do not? It's clear that these other agencies have found the data compelling enough to conduct an inspection, so how can the Task Force be the only ones to argue that the harms outweigh the benefits?
We believe these new recommendations regarding breast cancer are misguided, and should be seen as a warning to all preventive health in Canada. If we do not pay attention to sound reasoning and start using only the latest evidence that reflects advances in treatments and diagnostics used every day in our clinics, we risk falling behind other countries and witnessing a decline in our cancer outcomes.
As cancer doctors and researchers, none of us wants to be the 40-year-old woman in Canada with these guidelines, given that the late-stage, incurable breast cancer we see in oncology wards could potentially be prevented through screening.
Post a Comment for "Ignoring reason and evidence: Why new breast cancer guidelines advising against screening women in their 40s are misguided"