Androgen metabolism and apocrine differentiation in human breast cancer.

Metabolism of (7 alpha-3H)testosterone has been measured in 111 human breast cancers and compared retrospectively with the degree of apocrine differentiation in the tumors. Cancers in which apocrine characteristics were a marked feature metabolized significantly more testosterone precursor than those in which apocrine features did not predominate. Higher metabolism was accounted for by increased conversion to 5 alpha-reduced products such as 5 alpha-dihydrotestosterone and 5 alpha-androstanediols.