Primary pure small cell carcinoma of the urinary bladder that responded to carboplatin plus etoposide: a case report and review of the literature.

Primary pure small cell carcinoma of the urinary bladder (SCCB) is an extremely rare tumor and accounts for less than 1% of all malignant tumors of the urinary bladder. This tumor exhibits more aggressive behavior than bladder transitional cell carcinoma. Unfortunately, optimal treatment strategy for this malignancy is still unknown. We present a patient with metastatic primary pure SCCB (stage IV) who responded to carboplatin plus etoposide combination chemotherapy and discuss the relevant current literature.