Clinicians know the odds tend to be stacked against Black breast cancer patients. They have more dangerous and aggressive subtypes of breast cancer more frequently than white patients. Within breast cancer subtypes, Black patients tend to have worse outcomes compared to white patients, too. But what biological factors contribute to these disparities — and how much — is an open question.
Now, there’s evidence that ancestry correlates with key mutations that can shape the biology of certain tumors and how those tumors respond to treatments. Research published on [March 30] in the JAMA Network Open found that Black patients tended to have worse responses to pre-surgical chemotherapy in nearly every subtype of breast cancer, but the disparity was most dramatic in HR-negative and HER2-positive tumors. When they looked deeper, the researchers found Black patients were more likely to have tumors with mutations that are associated with treatment resistance.
That suggests biological differences may be contributing to health disparities alongside other, social reasons, said Dezheng Huo, a cancer epidemiologist at the University of Chicago and one of the authors of the study.
