Health disparities in breast cancer.

There has been a growing Black-White disparity in breast cancer mortality after a period of relative equivalence. Literature shows that Black Americans with breast cancer are less likely to receive optimal care compared with White Americans. Tumors in Black Americans are more likely to be poorly differentiated and estrogen receptor negative and exhibit a high S-phase fraction compared with tumors from White Americans. Differences in dietary habits, breast-feeding, and obesity account for some of the population differences in outcome among Black Americans.