Specific Binding of Estradiol and Dihydrotestosterone in Human Mammary Cancers¹

Estrogen and dihydrotestosterone receptors were detected by agar gel electrophoresis in 224 human mammary tumor biopsies. Approximately half of the tumor specimens revealed measurable amounts of estradiol receptors, whereas only 20% contained dihydrotestosterone receptors. The average concentration of spare estrogen receptors in primary tumors was markedly higher in the postmenopausal than in the premenopausal group, but this was not found to be the case for androgen receptors. The findings presented are discussed with regard to the clinical relevance of multiple assays for various types of receptors in a single tumor.