Metastatic urothelial carcinoma to the brain, spinal cord and spine: A contemporary multi-institutional clinicopathologic analysis of 24 cases.

Only case reports and small series of metastatic urothelial carcinoma (UCa) to the central nervous system (CNS) or spine have been published. We identified 24 cases at our institutions. The mean patient age was 64 years (range: 41-78 years) with a male predominance. Nineteen (79%) cases involved the brain, 3 (13%) and 2 (8%) cases involved the spinal cord and spine, respectively. Most cases (79%) were a single mass with a mean size of 2.8 cm (range: 0.9-5.5 cm). With the exception of 3 cases demonstrating micropapillary UCa, all metastases showed morphologic features of conventional UCa. Prior to CNS and spinal metastases, there was a history of UCa involving only the bladder in 16 (67%) patients, ureter in 1 (4%) patient, and kidney/renal pelvis in 1 (4%) patient. In 1 additional patient (4%) each, the primary tumor involved both bladder and ureter, bladder and kidney/renal pelvis, and ureter and kidney/renal pelvis, respectively. Three (13%) patients had no known primary site. In two patients, the diagnosis of primary UCa was made concurrently as the CNS metastasis, and ranged up to 30 years in other patients. Follow-up was available in 14 patients with a mean duration of 7 months (range: 0-23 months), and 4 patients died of disease. Both clinicians and pathologists should be aware that concurrent or late CNS or spine metastases may occur and could present as a solitary mass even over a decade after the initial diagnosis.