[Sarcomatoid carcinoma of the urinary bladder: report of a case]

The patient was a 78-year-old man with gross hematuria. A non-papillary and non-pedunculated tumor was found on the posterior wall of the bladder by cystoscopic examination. Total cystectomy with construction of ileal conduit was performed. Histologically, the tumor was composed of carcinomatous and sarcomatous elements. The carcinomatous element was compatible with grade 3 transitional cell carcinoma. The sarcomatous element was composed of osteosarcomatous, chondrosarcomatous pattern and undifferentiated malignant spindle cell component. Immunohistochemical examination demonstrated the presence of keratin, cytokeratin and epithelial membrane antigen in both carcinomatous and sarcomatous elements. Therefore, we diagnosed this tumor as sarcomatoid carcinoma. The patient has remained well without any evidence of recurrence for 10 months after operation.