Carcinosarcoma of the prostate in combination with adenocarcinoma of the prostate and adenocarcinoma of the seminal vesicles. A case report with immunocytochemical analysis and review of the literature

A unique triad of a carcinosarcoma and an adenocarcinoma of the prostate as well as an adenocarcinoma of the seminal vesicles in a 67‐year‐old man is reported. The carcinosarcoma was investigated by immunohistochemical methods. The mesenchymal parts of the sarcoma showed chondromatous differentiation expressed by S‐100 protein and vimentin. The undifferentiated epithelial elements of the carcinosarcoma reacted positively to the panepithelial antibody lu‐5 and to carcinoembryonic antigen (CEA). The adenocarcinoma of the prostate stained with antibodies to panepithelial antigen (lu‐5), prostatic acid phosphatase, prostate specific antigen and CEA, whereas the adenocarcinoma of the seminal vesicles reacted only to lu‐5 and CEA. The literature is reviewed.