Dehydroepiandrosterone sulfate and breast cancer risk.

It has been suggested that dehydroepiandrosterone (DHEA) and its sulfate ester, dehydroepiandrosterone sulfate (DHEAS), have a protective effect against breast cancer. In our investigation, DHEAS levels were measured in plasma obtained and frozen in 1972-1974 from 534 women aged 50-79 yr. This group, which has been followed for 15 yr, included 21 incident cases of breast cancer, 20 cases with earlier diagnosis, and ten cases with unknown date of onset who were identified from death certificates only. Two sets of analyses were done: one using all women and one which excluded women using estrogen. No significant differences in age-adjusted DHEAS levels were found between any case type and noncases. Age-adjusted rates of breast cancer by DHEAS tertile also showed no significant trends or differences among tertiles for any case type. A multivariate model in which the DHEAS level was adjusted for age, body mass index, estrogen use, and cigarette smoking status also showed no significant association between DHEAS and risk of breast cancer. These results do not support a protective role for plasma DHEAS in breast cancer risk in postmenopausal women.