Cytologic features of prostatic adenocarcinoma in urine: a clinicopathologic and immunocytochemical study.

Cells of adenocarcinoma of the prostate (ACP) are infrequently shed in urine. We examined the clinicopathologic features of 22 patients with ACP and tumor cells in urine. Patients typically were clinical stage C or D and had hematuria (13 cases, 59%) and/or obstruction (11 cases, 50%). Prostatic palpation or instrumentation preceded collection of 15 urine specimens. Histologically, tumors were high grade (Gleason score 7-10) and extensive, with involvement of prostatic ducts and acini (10 cases, 45%) and prostatic urethra (5 cases, 23%). Cytologically, the background was clean, and neoplastic cells appeared singly, in loose clusters, as large "casts," or, rarely, in papillary structures. The cells were small, round to oval, with a moderate amount of finely granular or vacuolated cytoplasm; nuclei were generally round with a thin, often irregular membrane, finely granular chromatin, and a single prominent nucleolus. Immunoperoxidase staining for prostatic acid phosphatase and prostate-specific antigen was useful in distinguishing ACP from transitional cell carcinoma.