Biennial Mammography Screenings Reduce Breast Cancer Mortality Disparities in Black Populations

Although biennial screenings from ages 45 to 74 years appeared to be the most efficient among Black patients with breast cancer, screenings that took place from ages 40 to 74 years were the most equitable.

Utilizing biennial mammography in Black patients with breast cancer who are 40 years of age helped to reduce disease-related mortality and resulted in a similar risk/benefit ratio to White patients who are screened biennially at ages 50 to 74 (B50-74), according to findings from a study published in Annals of Internal Medicine.¹

Although biennial screenings from ages 45 to 74 years (B45-74) appeared to be the most efficient among Black patients, screenings that took place from ages 40 to 74 years (B40-74) were the most equitable. Moreover, among the respective strategies, B40-74 yielded 32% more life years given (LYS) compared with 19% more disease-related deaths avoided when utilizing a B50-74 strategy; however, this required 45% more mammograms, leading to 52% more false positives.

“There is an increasing focus on eliminating race-based medicine,” lead author Christina Hunter Chapman, MD, MS, an adjunct assistant professor in the Department of Radiation Oncology at the University of Michigan, said in a press release.² “However, calls to end race-based medicine that ask for the immediate cessation of any discussion on race are not likely to eliminate racial disparities. Carefully selected solutions for health inequity may involve tailoring interventions to specific racial groups.”

A total of 9 strategies were evaluated that varied by starting ages—40, 45, and 50 years—and interval—annual, biennial, or a hybrid interval. The cohort included women in the United States who were born in 1980 and turned 40 in 2020. The population was followed starting at age 25 years.

When Black and White patients were screened utilizing a B50-74 strategy, investigators reported 17.62 deaths per 100,000 among Black patients compared with 14.33 among White patients, translating to an excess of 3.29 deaths in Black populations. However, when a B40-74 strategy was implemented, the deaths would decrease to 1.88 per 1000 or 15.74 per 100,000. This translated to a 57% reduction of racial disparity in mortality under the current screening guidelines.

“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,” senior author Jeanne S. Mandelblatt, MD, MPH, a professor of oncology and medicine at Georgetown Lombardi Comprehensive Cancer Center, said in a press release.

Secondary findings indicated that B40-74 remained equitable, with B45-74 appearing slightly more equitable when considering breast cancer deaths that averted false positives.

“In the future, the harms of racism in medicine may be better rectified by developing interventions that use more direct measures of racism instead of race. However, using socioeconomic status alone as a proxy for race would not be appropriate in a study like ours, given that racial disparities in breast cancer are observed across socioeconomic strata,” Chapman concluded.

References

1. Chapman CH, Schechter CB, Cadham C, et al. Identifying equitable screening mammography strategies for Black women in the United States using simulation modeling. Ann Intern Med. 2021;174:xxx-xxx. doi:10.7326/M20-6506
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 19, 2021. https://bit.ly/3aTORLW