Physicians and patients need more guidance to help them navigate the complex array of clinical factors and personal preferences that must be considered when deciding how best to individualize their approach to breast cancer mammography screening.
What makes the choice even more complicated is that the benefits of the screening are often overestimated, while harms are underestimated, say Nancy Keating, a professor of health care policy at Harvard Medical School and a physician at Brigham and Women’s Hospital, and Lydia Pace, HMS assistant professor of medicine and an internist at Brigham and Women’s.
In a JAMA Insights article, co-authors Keating and Pace summarize the current state of breast cancer screening in the U.S. The authors note that, despite the fact that the U.S. Preventive Services Task Force in 2009 (USPSTF) changed its recommendation for mammography to every two years for women aged 50 to 74 instead of annually beginning at age 40, there has been little change in U.S. screening practices.
They further point out that the USPSTF reiterated its recommendation in 2016 and that the American Cancer Society joined the task force in 2015 in advocating less routine use of mammography and a more individualized approach to screening.
In the Insights article, Keating and Pace highlight potential reasons for the limited change in mammography practices, such as clinicians emphasizing the benefits of screening without discussing the possible harms. “However, the most important contributor to limited uptake of these guidelines may be the challenge clinicians have in truly engaging patients in shared decision-making to individualize screening decisions,” the authors write.
The authors point out that although mammography screening has been shown to lower breast cancer death risk, the number of deaths prevented is very small.
“One of the greatest harms is overdiagnosis, which can subject some women to harmful treatment without any benefit,” Pace said. “Additionally, high rates of false positives and unnecessary biopsies should be considered as likely outcomes of breast cancer screening.”
The authors also raise concerns about current quality measures that assess the proportion of women who have had a mammogram in the past two years. They argue that “…given the modest benefits of mammography screening and real harms across all age groups, a more appropriate measure for accountability would be whether physicians assessed patients’ risk of breast cancer and engaged patients in shared decisions about when and how often to undergo mammography screening.”
“All patients should participate in shared discussions with their clinicians about mammography that consider their risk of cancer, summarize the benefits and harms of screening and take into account patient values and preferences,” Keating said.