A 47-year-old man presented with hematuria and dysuria. He was found t
o have a carcinosarcoma originating from a bladder diverticulum. He un
derwent a partial cystectomy and received postoperative chemotherapy.
One year later, he presented with a large local recurrence and died sh
ortly afterward. We believe this to be the second case of a carcinosar
coma originating in a bladder diverticulum.