[A case of carcinosarcoma of the urinary bladder]

We report a case of carcinosarcoma of the urinary bladder. A 50-year-old man visited our hospital with asymptomatic macroscopic hematuria as a chief complaint. Excretory urography revealed a filling defect in the right wall of the bladder, and subsequent cystoscopy revealed a non-papillary tumor above the right orifice. The patient underwent total cystectomy and had a neobladder constructed with the ileum (Hautmann's method). Microscopic examination showed a tumor composed of a mixture of transitional cell carcinoma and rhabdomyosarcoma. Immunohistochemical examination showed that the area of epithelium component was positive for cytokeratin and the non-epithelium area was positive for vimentin, there being no relationship between the two. The patient began complaining of coccyalgia 10 days after the operation. He died about 1 month after the operation because of the recurrence in the pelvic cavities.