Spinal seeding of a pilocytic astrocytoma in an adult, initially diagnosed 18 years previously.

Pilocytic astrocytoma (PA) is a slow-growing, well-circumscribed grade I glioma generally considered benign, with a low recurrence rate and an excellent prognosis following complete surgical resection. PA is the most common central nervous system glioma in the pediatric population and is rare in adults. We report a 26-year-old male with an intradural extramedullary PA at the thoracolumbar junction following subtotal cerebellar PA resection 18 years previously. Fifteen months after spinal PA resection, the patient is doing well, has regained the ability to stand independently, and has no evidence of any new or enlarging lesions. To our knowledge, this is the longest time reported from initial tumor resection of leptomeningeal dissemination to the distal spinal cord. PA patients with subtotal resection may benefit from continued follow-up for up to 20 years after the initial diagnosis and resection.