Small Cell Carcinoma of the Urinary Bladder. Report of two Cases and Review of the Literature

Undifferentiated small cell carcinoma of the bladder is a rare but aggressive subset of urinary tract neoplasms. Analogous to small-cell carcinoma of the lung, this tumor frequently exhibits neuroendocrine differentiation. We report the 92nd and 93rd case of small cell carcinoma of the bladder reported in the literature with characteristic cytologic, histologic, histochemical, and ultrastructural features. The patients were treated initially with chemotherapy, but after a brief clinical course died for progression of disease and for myocardial infarction, respectively. The pathologic and clinical features and therapeutic options of the cases described in the literature are reviewed.