Researchers from the Mass General Brigham have revealed that Black women face a higher risk of dying from breast cancer than white women across all tumor subtypes. The meta-analysis, published in the Journal of Clinical Oncology, shows that Black women’s risk of death varies from 17% to 50% higher depending on the type of breast cancer, underscoring the ongoing racial disparities in healthcare.
These findings suggest that factors beyond tumor biology, such as socioeconomic inequality, delays in diagnosis, and limited access to quality cancer treatment, contribute to these mortality differences.
“Black women who develop breast cancer are around 40% more likely to die of the disease than white women,” said senior author Erica Warner, a cancer epidemiologist at Massachusetts General Hospital.
“Our findings demonstrate that multiple, interacting factors contribute to disparities in breast cancer survival between Black and white women.” Warner highlights the need for comprehensive interventions at multiple levels to address these disparities, stating that efforts must involve healthcare systems, communities, providers, and patients alike to improve outcomes for Black women with breast cancer.
Breast cancer is not a single disease, but rather comprises multiple subtypes defined by the presence of hormone receptors like estrogen and progesterone, as well as proteins like HER2. These subtypes differ in their risk factors, treatment options, and prognosis. Warner’s team examined whether survival differences between Black and white women were consistent across all subtypes by analyzing data from 18 studies published between 2009 and 2022. These studies included data on 228,885 breast cancer cases, of which 34,262 were in Black women.
They found that Black women had worse survival outcomes for all breast cancer subtypes, but the size of these disparities varied. For hormone-positive tumors, which are typically more treatable, Black women faced a 34–50% higher risk of death. In contrast, for hormone-negative tumors—often considered more aggressive—the increased risk of death for Black women was 17–20%.
“These findings underscore a stark reality in our healthcare system: Black women are facing higher risks of death from breast cancer compared to their white counterparts, across all types of the disease. This disparity isn’t just about biology,” added co-author Paulette Chandler, MD, associate epidemiologist at the Brigham and Women’s Hospital. “It’s a call to action for healthcare providers, policymakers, and communities alike to confront these inequities head-on and strive for meaningful change in breast cancer outcomes.”
Warner suggests that these disparities may not have been previously observed for hormone-negative tumors due to the small number of cases in individual studies. Additionally, she notes that differences in the biological characteristics of certain tumor subtypes between racial groups may exist. “There may also be differences in the biological characteristics of some tumor subtypes between racial groups that our therapies are not attuned to, potentially because of underrepresentation of Black women in clinical trials,” Warner explained.
Despite these challenges, the researchers believe these disparities are not inevitable. They point to existing multilevel intervention programs that have successfully reduced gaps in cancer survival rates between Black and White women. These programs help patients navigate the healthcare system, address social needs, and track care milestones. National initiatives like ACCURE and Equal Hope aim to close the survival gap, while local efforts such as the virtual Equity Hub for Cancer Treatment in Boston seek to improve cancer care for underserved patients.
