Purpose: To review the current knowledge about breast cancer in black women--including epidemiology, risk factors, screening practices, pathology, clinical manifestations, treatment, and outcome--with emphasis on issues that might explain why the survival rate in this population of women is lower than that in white women.
Data sources: The MEDLINE database from 1966 to 1995 and the bibliographies of all related articles.
Study selection: Review articles and clinical studies related to all aspects of breast cancer in black women.
Data synthesis: The incidence of breast cancer is lower in black women (95.8 cases per 100 000 women) than in white women (112.7 cases per 100 000 women). Differences in reproductive factors may partially explain the lower risk for breast cancer among black women in the United States. Breast tumors in black women are consistently diagnosed at a more advanced stage of disease: Forty-two percent of black women present with cancer confined to the breast compared with 53% of white women. In addition, the cancers of black women tend to be more poorly differentiated and are less likely to be estrogen receptor positive. Treatment of breast cancer in black women appears to be similar to that in white women, but little is known about systemic therapy choices and efficacy. Overall, despite their lower risk for breast cancer, black women have a mortality rate from breast cancer similar to that of white women because they have a lower 5-year disease-specific survival rate (64% in black women compared with 80% in white women).
Conclusions: The discrepancy in survival rate between black and white women exists because black women have tumors that are more advanced at the time of diagnosis, because tumor biology in black women is different from that in white women (in particular, black women have a higher frequency of poorly differentiated tumors and a lower frequency of hormone receptor-positive tumors), and because of confounding comorbid conditions and socioeconomic factors. Current efforts to improve survival rates in black women with breast cancer should focus on community education, screening efforts, and early detection. As more information is gained about breast cancer treatment in black women, this may also be an important area for intervention.