46-year-old man with a spinal cord mass.

Medulloblastoma accounts for only 1% of all adult CNS tumors. Likewise, recurrence of adult medulloblastoma greater than 20 years after initial diagnosis is extremely rare.We describe a case of adult medulloblastoma with late relapse of disease. The patient was 24 years old when first diagnosed and was treated with total tumor resection and craniospinal radiation. At the age of 45, an enhancing 1.3 cm intradural extramedullary spinal cord lesion at T5 was discovered on MRI. This was presumed to be recurrent medulloblastoma in the form of drop metastasis and the patient was treated with spinal radiation. Several months following treatment, at the age of 46, a follow-up MRI demonstrated an enhancing 1.4 cm intradural extramedullary spinal cord lesion at T7. The lesion was resected and histopathologic examination was most consistent with medulloblastoma, late drop metastasis. Although rare, adult medulloblastoma recurring 20 years after initial diagnosis should always be considered in the main differential diagnosis when working up CNS lesions at or outside the primary tumor site.