A Case of Prostatic Duct Adenocarcinoma Closely Mimicking Urothelial Carcinoma in the Voided Urine Cytology

We report herein on a case of prostatic duct adenocarcinoma. An 84-year-old man was admitted to our hospital with dysuria and macroscopic hematuria. Cystoscopy of the lower urinary tract showed a papillary tumor in the prostatic urethra. In the voided urine cytology, tumor cells with a relatively high N/C ratio and hyperchromasia of the nucleus showed numerous irregular-sized aggregations.Histologically, the adenocarcinoma consisted of tall columnar tumor cells and a papillary pattern was seen. Immunohistochemically, the tumor cells were positive for PSA.Differentiation between prostatic duct adenocarcinoma and urothelial carcinoma depends on identification of the cellular columnar features and immunohistochemistry.