In response to the rising incidence of breast cancer in younger women and consistently high mortality rates among Black women, health experts have recently updated the standard guidance for mammograms. According to the New York Times, the U.S. Preventive Services Task Force now advises that women of all racial and ethnic backgrounds at average risk for breast cancer should start regular mammogram screenings at age 40, rather than age 50 as previously recommended.
The task force is known for issuing influential preventive health guidelines, and its recommendations are typically widely accepted in the United States. However, this new draft proposal marks a significant departure from previous advice. In 2009, the task force increased the suggested age for beginning routine mammograms from 40 to 50, due to concerns that early screening might cause more harm than good, potentially resulting in unnecessary treatments in younger women, including negative biopsies.
Recent breast cancer trends have been concerning, with an apparent increase in cases diagnosed in women under 50 and a persistent survival gap for younger Black women, who experience breast cancer mortality at double the rate of their white counterparts of the same age. Dr. Carol Mangione, the immediate past chair of the task force, stated that while the reasons for the increase in breast cancer among women in their 40s remain unknown, screening for this age group is likely to be more beneficial given the rising number of cases.
This updated recommendation affects over 20 million women in the United States aged between 40 and 49. In 2019, about 60% of women in this age group reported having had a mammogram in the past two years, compared to 76% of women aged 50 to 64 and 78% of women aged 65 to 74. The task force mentioned that there is insufficient evidence to make recommendations for women aged 75 and older.
For the first time, the task force has commissioned studies on breast cancer specifically among Black women, as well as all women, and is calling for more research to understand the factors contributing to racial disparities. The task force is also requesting a clinical trial to compare the effectiveness of annual and biennial screening among Black women.
Although breast cancer mortality has declined in recent years, it remains the second most common cancer among women after skin cancer and the second leading cause of cancer deaths, following lung cancer, among women in the United States.
Between 2000 and 2015, breast cancer diagnoses among women in their 40s increased by less than 1%. However, the rate increased by an average of 2% per year between 2015 and 2019, according to the task force. The causes for this increase are not completely understood, but factors such as delayed childbearing or not having children at all may be contributing to the rise, suggests Rebecca Siegel, senior scientific director of surveillance research at the American Cancer Society. Having children before age 35 and breastfeeding are known to reduce the risk of breast cancer.
Year-to-year variations in diagnosis rates are significant, and some researchers propose that the increase in younger women might simply be due to increased screening, says Dr. Steven Woloshin, professor of medicine at Dartmouth University. Frequent screening can itself be harmful, leading to unnecessary biopsies that cause anxiety and treatment for slow-growing cancers that would never have been life-threatening.
The 2009 task force guidance that recommended women start getting regular mammograms no later than age 50 faced heavy criticism from patients and advocacy groups who feared malignancies would be missed among younger women and suggested that the recommendation was driven by a desire to reduce healthcare costs. At that time, the panel also advocated for longer intervals between mammograms, recommending one every two years instead of annual scans, a recommendation that still stands today.
IMAGE CREDIT: US Navy.
