Sarcomatoid Carcinoma of the Urinary Bladder.

Sarcomatoid carcinoma of the urinary bladder (SCUB) is a rare and aggressive subtype of bladder cancer that has a poor prognosis. Limited information is available regarding its clinical features and appropriate treatments. A systematic literature search for published reports on SCUB was performed in the MEDLINE database using the key words "bladder cancer," "sarcomatoid carcinoma," and "carcinosarcoma.". The search resulted in the identification of 276 reports published from January 1960 to January 2014, of which 40 were ultimately included in the present review. No prospective study or clinical trial of SCUB was reported in English language studies. Of these studies, 2 cancer registry studies and 13 large case series, which had included ≥ 8 cases were identified. Seven single-institution studies contained adequate clinical follow-up information, and the rest had mainly focused on the pathologic features of the disease. Both the registry and the single-institution studies showed that patients with SCUB presented with a high histologic grade, advanced-stage disease, and a poor prognosis. Comparing the single-institution studies to the Surveillance, Epidemiology, and End Results cohorts, significant differences were found in the age at diagnosis, male-to-female ratio, tumor stage, treatment pattern (cystectomy, radiation, and chemotherapy), and outcomes, likely reflecting differences in referral and practice patterns. The tumor stage was identified as a significant predictor for cancer-specific survival. The results of the present study suggest that SCUB is not as rare as previously thought. Patients with SCUB should be referred to specialists or centers with extensive experience with this rare and serious disease.