Race and clinical outcome in breast cancer in a series with long-term follow-up evaluation.

Abstract

PURPOSE To compare the outcome of African American (AA) and Caucasian (C) breast cancer patients who had equivalent disease extent and were similarly treated. PATIENTS AND METHODS We compared prognostic characteristics, treatment, and outcome of 1,037 C and 481 AA breast cancer patients treated with mastectomy between 1946 and 1987. The median follow-up duration was 15.6 years. RESULTS During the study period, there was a successive increase in the percent of patients who presented with early breast cancer. Between 1980 and 1987, 35.1% AA versus 47.6% C patients had < or = 2-cm tumors and 50.0% AA versus 61.9% C patients were node-negative, while between 1946 and 1959, 27.7% AA and 31.3% C had < or = 2-cm tumors and 41.5% AA versus 40.4% C patients were node-negative. The treatments were similar during the study period. The 20-year disease-free survival (DFS) rate of AA compared with C patients with node-negative < or = 2-cm, 2.1- to 4-cm, and greater than 4-cm tumors and of patients with one to three and > or = four positive nodes was not significantly different. Equal-size tumors had similar proportion of positive axillary nodes in AA compared with C patients. The DFS for AA patients compared with C patients was similar in the periods 1946 to 1959, 1960 to 1969, and 1970 to 1979, but was lower between 1980 and 1987 (P = .02). In multivariable analysis, race was not a significant variable. CONCLUSION In this large group of uniformly treated breast cancer patients, race was not an independent factor that influenced outcome. The racial differences seen between 1980 and 1987 are likely because of a larger percent of greater than 2-cm and node-positive tumors in AA patients. Education and access to early diagnosis should reduce or eliminate the racial differences seen.