Carcinoma within urethral diverticula.

Because diagnosis of urethral diverticulum is often elusive the presence of a tumor within the diverticular cavity may be overlooked until it has grown beyond the confines of the diverticulum. A search of the medical records from 1940 to 1975 at the University of California Medical Center in San Francisco and Alta Bates Hospital in Berkeley has revealed only 3 cases of carcinoma within a urethral diverticulum. Two are presented here and the third was reported by Hinman in 1960. The paucity of cases in the literature reflects the rarity of such location for the tumor--or, perhaps, rather its evasive diagnostic nature. Undoubtedly, many cases are unreported but the important message for the clinician is that he suspect a urethral diverticulum (with the possibility of underlying neoplasm) in any patient with unexplained persistent irritative symptoms of the lower genitourinary tract.