Peer Reviewed

Breast Cancer Screening

Earlier Mammography Reduces Breast Cancer Mortality in Black Women

Biennial mammography screening from age 40 years instead of age 50 years for Black women may significantly reduce breast cancer deaths in this population, according to the results of a recent analysis of the Cancer Intervention and Surveillance Modeling Network (CISNET) study.1

In an effort to examine racial differences in breast cancer screening and subsequent outcomes, the researchers conducted a simulation model to test various screening strategies at different ages. Included were race-specific inputs for subtype distribution, breast density, mammography performance, age-, stage-, and subtype-specific treatment effects, and non-breast cancer mortality for a cohort of Black and White women born in the United States in 1980.

Outcomes of the model included benefits, harms, and benefit-harm ratios by race. Life-years gained (LYG), breast cancer deaths averted, and mortality reduction were among the benefits, whereas mammographies, false positives, and overdiagnoses were among the harms.

The results indicated that screening Black women from age 40 to 74 years was the most equitable to the benefits and harms of screening White women according to the current guidelines. Further, screening Black women from age 45 to 74 years was the most efficient screening strategy.

When compared with White women with a similar LYG mammogram, screening Black women 10 years earlier resulted in a 57% reduction in Black-White mortality disparities.

“Black women have higher rates of aggressive cancers at younger ages than White women, and treatments for those types of tumors are not as effective. However, even when we account for cancer subtypes, mortality is higher for Black women largely due to factors that are ultimately rooted in racism,” concluded study author Jeanne S. Mandelblatt, MD, MPH, in a press release.2 “Therefore, in our analyses we accounted for differences in treatment attributable to racism, including access to medication, delays in treatment, dose reductions, and discontinuation of treatment—all factors that have been shown to be suboptimal more often in Black than White women.”


—Leigh Precopio



  1. Chapman CH, Schechter CB, Cadham CJ, et al. Identifying equitable screening mammography strategies for Black women in the United States using simulation modeling. Ann Intern Med. Published online October 19, 2021.
  2. Starting mammography at age 40 would reduce disparities in deaths for Black women. News release. Georgetown Lombardi Comprehensive Cancer Center; October 18, 2021. Accessed October 20, 2021.