Small cell carcinoma of the bladder in transplant recipients: a report of 2 cases.

Small cell carcinoma (SCC) of the urinary bladder is a rare disease accounting for 0.5% to 0.7% of all primary bladder cancers. Transplant recipients are a special subset of patients with increased risk for various urologic malignancies, including transitional cell carcinoma of the bladder. However, to the best of our knowledge, a SCC of the urinary bladder has not been reported in transplant recipients. We report what we believe are the first 2 reported cases of transplant recipients with SCC of the bladder. Small cell carcinoma was diagnosed 5 years after transplantation in both patients and they died due to metastatic SCC. Our report emphasizes the highly aggressive nature of SCC and also the rapid progression seen in transplant recipients.