Adenosquamous carcinoma of prostate

A case is reported of metastatic adenosquamous carcinoma that developed in a patient one year after diagnosis of adenocarcinoma of the prostate by transurethral resection of the prostate (TURP). Prostatic origin of the neoplasm was proved by immunoperoxidase staining for prostatic acid phosphatase in the metastases as well as demonstration of both glandular and squamous differentiation in tumor within the prostate on repeat TURP. This change in tumor differentiation occurred despite the fact that the patient had received no estrogen or radiation. The metastases showed remarkable response when the patient later began diethylstilbestrol (DES) therapy.