Adenosquamous carcinoma of the prostate.

A case of the rare adenosquamous carcinoma of the prostate is herein presented. The divergent epithelial differentiation of the tumor was shown by conventional microscopy, immunohistochemistry, and ultrastructural studies. In previously described cases as well as in the present one, the tumor appeared several years following treatment of an ordinary prostatic adenocarcinoma by radiotherapy. It is proposed that adenosquamous carcinoma of the prostate arises from pluripotent stem-cells, with irradiation playing an etiopathogenetic role.