Cytological diagnosis of small cell carcinoma of urinary bladder in a patient with CLL

Small cell carcinoma of the urinary bladder [SCCUB] is an extremely rare bladder malignancy characterized by an aggressive clinical behavior. So, it is important to diagnose this high grade disease by urinary cytology. We report a case of SCCUB in an old man with chronic lymphocytic leukemia [CLL] in remission, while bladder tumor was diagnosed by cytology. With this article, we aimed to review and to update the literature concerning this tumor.