[Signet ring cell carcinoma of the urinary bladder: a case report].

A 69-year-old man was admitted complaining of macroscopic hematuria. Cystoscopic examination revealed a non-papillary tumor at the anterior wall of the urinary bladder. A pelvic computed tomographic (CT) scan showed marked thickening of the anterior bladder wall. Radical cystectomy and bilateral ureterocutaneostomy were performed. Histopathological examination revealed signet ring cell carcinoma of the bladder, stage pT3bN1M0. This tumor is rare, and has a poor prognosis. Our patient has been well without any evidence of disease 6 months after surgery. To the best of our knowledge, there are 44 reported cases, and our case is the 45th in Japan.