Clinical Features of Sarcomatoid Carcinoma (Carcinosarcoma) of the Urinary Bladder: Analysis of 221 Cases

Background. Urinary bladder sarcomatoid carcinoma (carcinosarcoma) is rare. The objective of this study was to examine the epidemiology, natural history, and prognostic factors of urinary bladder carcinosarcoma using population-based registry. Methods. The Surveillance, Epidemiology, and End Results (SEER) Program database was used to identify cases by tumor site and histology codes. The association between clinical and demographic characteristics and long-term survival was examined. Results. A total of 221 histology confirmed cases were identified between 1973 and 2004, this accounted for approximately 0.11% of all primary bladder tumors during the study period. Median age of the patients was 75 years (range 41-96). Of the patients with a known tumor stage (N = 204), 72.5% had a regional or distant stage; 98.4% of patients with known histology grade (N = 127), had poorly or undifferentiated histology. Multiple primary tumors were indentified in about 40% of study subjects. The majority of patients (95.9%) received cancer directed surgery, 35.8% had radical or partial cystectomy, 15.8% of patients received radiation therapy combination with surgery. The median overall survival was 14 months (95% CI 7-21 months). 1-, 5-, and 10-year cancer specific survival rate were 53.9%, 28.4% and 25.8%. In a multivariate analysis, only tumor stage was found to be a significant prognostic factor for disease-specific survival. Conclusions. Urinary bladder carcinosarcoma commonly presented as high grade, advanced stage and aggressive behavior with a poor prognosis. Emphasis on early detection, including identification of risk factors is needed to improve the outcome for patients with this malignancy.