Sarcomatoid urothelial carcinoma of the bladder: a contemporary clinicopathologic analysis of 37 cases.

INTRODUCTION: Sarcomatoid urothelial carcinoma is a dedifferentiated biphasic tumor that exhibits morphological and/or immunohistochemical evidence of epithelial and mesenchymal differentiation. In this series, we analyzed the clinicopathologic features of this rare variant of urothelial carcinoma.
MATERIALS AND METHODS: A search was made through our surgical pathology files and consultation files of the senior author for cases of sarcomatoid urothelial carcinoma of the bladder from 2005-2014. All the slides were retrieved and re-reviewed, and clinical data was also obtained including follow up.
RESULTS: Thirty-seven cases of sarcomatoid urothelial carcinoma of the bladder were identified. Mean patient age was 71 years (range: 51 to 88 years). Twenty-six of 37 (70%) patients were male and 11/37 (30%) patients were female. Twenty-five cases were from cystectomy/cystoprostatectomy specimens, 8 cases from transurethral resection of bladder tumor specimens and 4 cases were from biopsy specimens. The mean tumor size was 5 cm (range: 1.4 cm to 13.0 cm). Four of 37 (10%) cases had focal heterologous components; 1 case with both chondroid and osteoid, 2 cases with chondroid and 1 case rhabdoid elements. Twenty-one of 37 (56%) patients died within a year of presentation.
CONCLUSIONS: Sarcomatoid urothelial carcinoma of the bladder is more prevalent in males, with the mean age of 71 years in our series. Smoking is an important risk factor. Sarcomatoid urothelial carcinoma is an aggressive variant of urothelial carcinoma which commonly presents at an advanced stage, and over 50% of patients in our series died of disease within 1 year of presentation.