Carcinosarcoma of the bladder.

We present 2 cases of carcinosarcoma of the bladder. These tumors are considered as true admixtures of epithelial and mesenchymal neoplastic cells rather than 2 separate neoplasms that touch or marginally invade each other. Although the etiology of this tumor is unclear it tends to be aggressive and probably requires an early radical operation with adjuvant radiotherapy and chemotherapy.