ETHNIC-DIFFERENCES IN RISK AND PROGNOSTIC FACTORS FOR BREAST-CANCER

Background. Poor survival among African American patients with breast cancer has been attributed to low socioeconomic status and lack of acc ess to health care. However, Hispanics of equivalent socioeconomic sta tus and health care access exhibit much higher survival rates, almost comparable to whites. This suggests that biologic differences play a r ole in differences in breast cancer survival in addition to socioecono mic and health care access factors. Methods. The authors studied clini cal and molecular differences between patients with breast cancer of d ifferent ethnicity to determine biologic explanations for the observed differences in survival. Consecutive patients scheduled for breast bi opsies were identified preoperatively and were interviewed, Blood was withdrawn for serum marker measurements, and tumor specimens collected at frozen section diagnosis were analyzed by flow cytometry, hormone receptor concentration, tumor grade, and Ki-67 nuclear antigen, HER-2/ neu, and epidermal growth factor oncoprotein expression. Results. Age, age at menarche, number of lymph nodes with metastasis, estrogen and progesterone receptor levels, ploidy status, S-phase, Ki-67, HER-2/neu expression, tumor grade, epidermal growth factor receptor expression, lipid-associated sialic acid (LASA), and carcinoembryonic antigen lev el were not significantly related to ethnicity. African Americans pres ented at a significantly more advanced stage and with significantly la rger tumors. They were significantly heavier and had a significantly h igher mean Quetelet's index and a significantly higher number of pregn ancies and number of live births. Whites and Hispanics were significan tly older at menopause. Conclusions. The molecular indices associated with breast cancer prognosis do not differ significantly among whites, African Americans, and Hispanics, suggesting that the reported differ ences in survival among these groups are not due to biologic differenc es in breast cancer among ethnic groups.