Inverted papillary carcinoma of the urinary bladder.

A 47-year-old man presented with an inverted papillary carcinoma of the urinary bladder. Cystoscopy revealed an approximately 2 cm mass, with a small stalk and smooth surface, which was situated just medial to the right ureteral orifice. Transurethral resection of the tumor was performed on July 25, 1983. Malignant changes were recognized in the epithelial cords in the resected specimen. This is in contrast to the general view that inverted papilloma of the urinary bladder is benign in nature. The authors believe that careful pathologic examination should be done when an inverted type tumor of the urinary tracts is found. No recurrence has been recognized as of September 11, 1987.