Social and biological factors in relation to survival among black vs. white women with breast cancer.

Longer survival for white women than black women with breast cancer has been observed even when relative survival rates are used and stage at diagnosis is controlled. This study compared prognostic factors in relation to survival for 144 white women and 67 black women with breast cancer diagnosed 1969 to 1979 and identified through the tumor registry. Data were obtained from medical records, the registry, death certificates, and pathology files. Median survival was 7.5 years for whites, vs. 5.6 years for blacks. Significant differences between races were also observed for histological type and grade of tumor, presenting symptoms, and health status at diagnosis. Although Cox multiple regression analyses showed pathological stage at diagnosis and number of positive nodes to be the best predictors of survival in both whites and blacks, the differences in histological type observed in this sample merits further research; blacks have fewer well-differentiated tumors, the type associated with positive estrogen receptors and with better survival.