Mammogenesis in transsexuals

Abstract

Photographs of modest to significant breast development in male transsexuals illustrate the range of male mammary tissue response, not strictly dose related, to hormonal feminization by exogenous estrogens and progestins, alone or in conjunction with castration. The histology of male mammary tissue is characterized in gynecomastia of varied etiology and in response to estrogen administration, with particular reference to lobule and acini formation. Breast cancer is discussed in relation to both therapeutic and transsexual hormonal feminization of men. It does not appear that estrogens induce breast cancer in men.