Racial differences in breast cancer survival: the effect of residual disease.

ABSTRACT

BACKGROUND: A survival difference has been seen in numerous studies between African-American (AA) and Caucasian (C) women with breast cancer. The purpose of this study was to elucidate the differences in patient characteristics and outcomes between AA and C women with breast cancer in our population. METHODS: We performed a retrospective analysis of 1345 women with newly diagnosed breast cancer who were entered into our tumor registry from October 1980 to December 1998. RESULTS: The association between race and stage at presentation was significant, as was the difference in the overall median survival between C and AA women. The data revealed no significant differences in survival between C and AA women presenting with Stage I or II disease. However, the differences between the median survival times for AA and C women presenting with Stage III and IV disease were both highly significant. A significantly lower percentage of AA women became "disease free" after initial therapy as compared with C women (P < 0.001). Interestingly, when data were stratified by stage, only in Stage III and IV were there significant differences between the races for becoming disease free. CONCLUSIONS: AA women tend to present at a later stage and have poorer survival from later-stage disease as compared with C women. The poorer survival appears to be related to the decreased ability to achieve disease-free status in AA women with advanced disease. The underlying causes of this difference in treatment outcome need further evaluation.