by Lisa Jarvis
October is Breast Cancer Awareness Month, as I was reminded over the weekend when a server offered me a special rose-colored cocktail to benefit a local cancer ward. I didn’t need that (delicious) beverage to be reminded that breast cancer is still the most common cancer among women. But it did make me think about how, despite decades of Pink Octobers, little has changed in our approach to breast cancer screening.
Recommendations for how often to screen have shifted in recent years, but guidelines are still written for women at average risk. Oncologists now have so much more information on who is at risk for more aggressive cancers, or ones that strike at a younger age. So why aren’t women screened based on their individual risk?
“In an aspirational world, we would like our guidelines to be really personalized or precision-based and adaptable over time,” says William Dahut, chief scientific officer of the American Cancer Society.
Such guidelines would consider factors like genetics, breast density and lifestyle choices when guiding how early and how often each person is screened, and shape the interventions to lower a woman’s risk of developing cancer. A more tailored approach could both save lives and prevent low-risk women from undergoing unnecessary procedures from incidental findings.
Modernizing mammography recommendations to better incorporate someone’s cancer risk might not sound like a radical proposition — after all, people happily accept a doctor’s instructions to not come back for five or seven or even 10 years based on what was found in their most recent colonoscopy. But changing the paradigm in breast cancer screening turns out to be frustratingly controversial, a reality no one knows better than Laura Esserman, director of University of California San Francisco’s Carol Franc Buck Breast Care Center.
Since 2016, Esserman has led a massive trial called Wisdom (for Women Informed to Screen Depending on Measures of Risk) to test the theory that a personalized approach could further reduce death rates — and also spare women unnecessary biopsies and treatment. The study is enrolling some 100,000 women, who are offered either standard or personalized screening approaches.
It’s an effort that elicits emotions ranging from doubt to full-blown vitriol. Some bristle at meddling with an approach that has undeniably saved hundreds of thousands of lives. Deaths from breast cancer have fallen by 43% since 1989, an improvement attributed in large part to a combination of better drugs and better screening.
But in the past decade, that decline has started to level off. While efforts to improve adherence to screening and invent better treatments could help, the field might also benefit from acknowledging the current imperfections in screening.
As Esserman points out, many cancers aren’t actually caught during a routine screen. In a long-running study to test multiple treatments for aggressive forms of breast cancer, she and her colleagues found that 84% of cancers were originally detected in women too young to be captured by current guidelines, who missed a recommended mammogram or, in the majority of cases, who were diagnosed between screens because they were experiencing symptoms. Esserman says that same pattern was found in a second iteration of the trial. “The data really point to the fact that we have to be smarter,” she says.
Esserman’s trial is testing whether it could work to identify the people with the highest risk and bringing them in earlier and more often, and conversely, to allow low-risk people to come in less often. The full data are still more than a year away, but already she’s found that family history is not always a reliable predictor of someone’s genetic risk of breast cancer — a fact that suggests now inexpensive genetic tests should be widely offered.
For now, women must navigate what feels like constantly shifting (and sometimes conflicting) advice about when to start screening.
The best plan for someone without a known risk factor is to start getting mammograms at 40, and certainly get annual screens by 45. Some people should start earlier — anyone carrying a mutation like BRCA1 or BRCA2, or with family members that had cancer young, or with dense breasts. Dahut says the rule of thumb is to get that first screen a decade earlier than when your relative was diagnosed — so if your mom had breast cancer at 47, you’ll want to get a mammogram at 37, and you should talk to your doctor about additional imaging like an MRI.
That can feel confusing to some, and admittedly will become even more nuanced if the industry does move to personalized screening. But women would have a lot more knowledge, too — about their individual risk and the benefits of following advice tailored to it. That sounds like a rational, even empowering approach to managing your health.
