Interracial differences in sex-steroid receptor status of breast cancers.

Fifty-three consecutive patients were studied to determine whether significant racial differences in estrogen receptor (ER) and progesterone receptor (PR) status existed. Unexpectedly, a significant difference was found between the percentages of premenopausal black and white women expressing ER-positivity (ie, 100 percent black women vs 60 percent white women; P <0.05). No significant differences were found between the races in respect to tumor stage, tumor size, tumor differentiation, absolute or mean ER and PR values. These findings differ from previously reported studies and suggest that patients of similar socioeconomic status do not demonstrate ER and PR differences based on race alone. Further prospective studies are indicated.