Solitary cerebellar metastasis from transitional cell carcinoma of bladder.

Brain metastasis from transitional cell carcinoma of the bladder is unusual, occurring most often in the presence of widespread systemic metastases. We report on a patient who presented with an isolated cerebellar metastasis and recurrent carcinoma of the bladder, after treatment with local excision and intravesical thiotepa. Further evaluation failed to demonstrate other distant metastases. Excision of the cerebellar lesion revealed transitional cell carcinoma identical to the original bladder tumor. In a review of the literature, we found reports of two similar patients in whom a solitary cerebellar lesion was the first sign of metastasis from carcinoma of the bladder; neither patient had evidence of other distant metastases, and neither previously had received systemic chemotherapy. These observations indicate that central nervous system metastasis from carcinoma of the bladder, while rare, should be considered in the differential diagnosis of solitary intracerebellar lesions in such patients.