Starting mammography screening at age 40 years in Black women could decrease breast cancer deaths
Breast cancer deaths could be cut by starting mammography screening in Black women 10 years earlier than in White women, a modeling study predicted.
A modeling study suggested that mammography screening every other year starting at age 40 years in Black women could cut cancer deaths by 57% while maintaining the same level of benefits and harms as seen from screening White women from ages 50 to 74 years.
Researchers from the National Cancer Institute-funded Cancer Intervention and Surveillance Modeling Network (CISNET) developed a model that projected the lifetime impact of digital mammography screening at different starting ages and screening intervals for women born in the U.S. in 1980. The model compared such benefits as number of life-years gained by early detection and breast cancer deaths averted to potential harms such as false positives or radiation exposure. The model used data about breast density, distribution of breast cancer molecular subtypes, age, stage at which treatment is started, and nonbreast cancer mortality in Black and White women. As a proxy for racism, researchers considered real-world treatment effectiveness based on factors such as access to medication, delays in treatment, dose reductions, and discontinuation of treatment. Results were published Oct. 19 by Annals of Internal Medicine.
The study found biennial screening from ages 45 to 74 years was most efficient for Black women, whereas biennial screening from ages 40 to 74 years was most equitable. If Black and White women were screened biennially from age 50 to 74 years, there would be an excess of 3.29 deaths among the former group, the study found (17.62 vs. 14.33 deaths per 1,000 persons). In contrast, if biennial screening was initiated in Black women beginning at age 40 years, deaths would decrease by 1.88 per 1,000 women, to 15.74, removing 57% of the racial disparity in mortality expected under current guideline screening, or 1.88 of 3.29 excess deaths, the researchers found.
The author of an accompanying editorial stated that classification of race may oversimplify the issue, as crude race categories used by physicians may cause more harm than just the proximal harms outlined in the research. However, as this study showed, a failure to consider race could perpetuate breast cancer racial disparities.
“Medicine needs to transform its data and descriptive statistics,” the editorial stated. “If we think human differences are important and should inform medical practice, then we need to invest the effort required to map and understand those differences.”