Mortality from breast cancer is markedly higher in African American
women as compared to white women in the United States, in part because they are
more likely to be diagnosed with estrogen receptor-negative tumors (ER-negative tumors), which are more
aggressive and difficult to treat.
African American women are also diagnosed with breast cancer at younger ages.
Black women under the age of 45 are at increased risk for an aggressive form of breast cancer if they experienced a high number of pregnancies, never breast fed, and/or had higher waist-to-hip ratio. These findings appear in Cancer Epidemiology, Biomarkers, & Prevention.
They evaluated the relation of reproductive factors, measures of body size, and other factors to incidence of ER-negative and ER-positive breast cancer in both younger and older women.
"Very little is known about how young women can reduce their personal risk of ER-negative breast cancer," said Kimberly Bertrand, epidemiologist at the Slone Epidemiology Center at Boston University and assistant professor of medicine at Boston University School of Medicine, who led this study. "Most exciting among our findings is that two of the factors we found to be important - breastfeeding and higher waist-to-hip ratio - are modifiable, which suggests opportunities for risk reduction or prevention."