[Transitional carcinoma in congenital diverticulum of the bladder]

The author presents a case of an urothelial tumour in a vesical diverticle of an adult 64 years old man. The rareness which justifies its publication is based on the fact that it was the question of a congenital diverticle (admitting that the presence of a complete muscular stratum ratifies such character). In spite of a clearly radical surgery the fast dissemination of the tumor which caused the patient's death in a few months could not be avoided. The special pathogenic and evolution characteristics of the tumorations in this localization are briefly analyzed.