Racial Differences in Risk of Aggressive Breast Cancer After Ductal Carcinoma in Situ
Posted: Friday, June 28, 2019
Among women with ductal carcinoma in situ, African American and Asian women may be at a higher risk than white women of developing biologically aggressive invasive breast cancer, according to findings published in CA: A Cancer Journal for Clinicians. Ying Liu, MD, PhD, of the Alvin J. Siteman Cancer Center and the Washington University School of Medicine, St. Louis, and colleagues noted that although the genetic and molecular features underlying this discrepancy are undetermined, the findings provide biologic context for studying inherent racial differences.
“A better understanding of race‐associated biological and nonbiological differences in the progression of [ductal carcinoma in situ] will help to distinguish high‐risk patients with [ductal carcinoma in situ] from low‐risk patients with [ductal carcinoma in situ] and improve personalized treatment to reduce the disproportionate burden of breast cancer in black women,” the authors concluded.
The authors identified 163,892 women with incidents of ductal carcinoma in situ between 1990 and 2015 from the Surveillance, Epidemiology, and End Results data sets. Of the women selected, 10.5% were black, 9.8% Asian, and 8.6% were Hispanic. Cox proportional hazards were utilized to estimate hazard ratios and invasive breast cancer by the hormone receptor status and 21-gene recurrence scores.
During a median follow-up of 90 months, 8,333 of the women developed invasive breast cancer. For black and Asian women, the adjusted hazard ratio of subsequent estrogen receptor–negative and progesterone receptor–negative breast cancer was 1.86% and 1.40%, respectively, when compared with white women. The authors found that these associations were stronger than associations for estrogen receptor–positive and/or progesterone receptor–positive subtypes.
The investigators reported that black patients were more likely than white patients to have a 21-gene recurrence score of 26 or higher (hazard ratio = 1.38). And no significant difference was found in the risk of subsequent breast cancer subtypes among Hispanic women.
Disclosure: The study authors reported no conflicts of interest.
