Renal carcinosarcoma: case report and review of literature.

Carcinosarcoma is a malignancy that occurs very rarely in the renal pelvis, and only a very limited number of cases has been documented. These tumors are composed of both malignant mesenchymal and epithelial elements. Unlike the cases described so far, this carcinosarcoma of the renal pelvis was characterized by quick recurrence, following complete surgical resection. Carcinosarcomas of the renal pelvis are known to be rapid in progression and associated with a poor prognosis. They usually metastasize soon after surgery, but very little information is available on the histologic types that characterize the recurrent tumors. We presented a histologically proven case of renal carcinosarcoma extending from renal pelvis. Convalescence was uneventful, and fifteen months after the operation, he is alive with no recurrence or metastasis. If a rapidly growing tumor is detected that seems to originate from the kidney with extension to ureter and bladder, carcinosarcoma should be included in the differential diagnosis.