Prognostic indices in breast cancer are related to race

African-American (AA) women have a higher mortality from breast cancer than Caucasians (C). This may be attributed to stage of disease at presentation, but specific prognostic factors are not well identified. We sought to identify prognostic factors in our database of early-stage (stage I and II) breast cancer from 1990 to 1999. There were 153 tumors in 150 AA women and 773 tumors in 760 C women. Prognostic factors are listed according to race with relative risk (RR) and 95 per cent confidence intervals. AA women presented significantly more often than C women under the age of 50 years (RR = 1.8) with palpable disease (RR = 1.3), higher-grade tumors (RR = 1.5), more estrogen receptor-negative disease (RR = 1.7), more progesterone receptor-negative disease (RR = 1.4), higher proliferation indices (RR = 1.9), and more lymph node-positive disease (RR = 1.6). Many of these adverse prognostic features persisted in "good" prognostic groups, i.e., those women over the age of 50 years with tumors <20 mm and having node-negative disease. We conclude that prognostic factors are related to race with AA women presenting at an earlier age and more often with palpable disease. More importantly AA women presented significantly more often with higher-grade tumors, hormone receptor-negative tumors, higher proliferation indices, and node-positive disease. These findings may explain a higher breast cancer mortality in AA women.