A Perfect Storm: Tumor biology and genomics
These results in African American patients highlight the need for further study of breast cancer genomics in minority populations. However, Armstrong et al.15 illuminated the existence of racial/ethnic disparities in patterns of referral to cancer risk clinics. In their study, African American women with a family history of breast or ovarian cancer were significantly less likely to undergo genetic counseling for BRCA1/2 testing than were white women with this family history. The results of this study were noteworthy for the magnitude of the disparity, with white women having almost five times greater odds of undergoing this clinically important evaluation. More than two decades after BRCA1 and BRCA2 genes were identified, larger studies are still needed in diverse populations to derive true estimates of the burden of mutations in both genes in underserved and understudied populations.
Although these differences in tumor biology and genomics tell part of the mortality disparity story, there is more to be told. In a study of African American and white patients in South Carolina, Adams et al.16 determined survival rates by ethnicity that were adjusted for disease stage and other prognostic characteristics. After they controlled for age, stage, ER, and HER2 expression as well as insurance status, African American women still had a twofold excess risk of death from breast cancer. Thus, in addition to differences in the innate characteristics of the breast tumors, racial differences in patterns of care for women with breast cancer must be considered in unraveling the observed disparity in mortality. The third installment of this series will discuss the second element of the perfect storm – patterns of care.
Other installments of this column can be found in the Related Content box.
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Bobby Daly, MD, MBA, is the chief fellow in the section of hematology/oncology at the University of Chicago Medicine. His clinical focus is breast and thoracic oncology, and his research focus is health services. Specifically, Dr. Daly researches disparities in oncology care delivery, oncology health care utilization, aggressive end-of-life oncology care, and oncology payment models. He received his MD and MBA from Harvard Medical School and Harvard Business School, both in Boston, and a BA in Economics and History from Stanford (Calif.) University. He was the recipient of the Dean’s Award at Harvard Medical and Business Schools.
