Spinal Pilocytic Astrocytoma in an Elderly Patient

OBJECTIVE: Astrocytomas are the most common intramedullary spinal cord tumor in pediatric and adolescent patients and the incidence decreases with age. There are very few cases of spinal pilocytic astrocytomas (World Health Organization grade 1) reported after the fourth decade. We report the oldest known case of a pathologically confirmed spinal pilocytic astrocytoma. METHODS: A 78-year-old woman presented with 12 months of bilateral lower extremity numbness. Magnetic resonance imaging revealed cord edema extending from C6 to T4. There was a 12-mm enhancing intramedullary lesion at the C7-T1 level with an associated cyst. Several years prior, she had seen a neurologist for lower extremity numbness and was diagnosed with peripheral neuropathy. RESULTS: She underwent C7-T1 laminectomy with partial resection of the spinal cord tumor and drainage of the cyst. Pathologic examination demonstrated a mildly cellular proliferation of astrocytes set in an eosinophilic fibrillar background. There were numerous Rosenthal fibers and prominent vasculature. There were no malignant features. The pathologic diagnosis was consistent with pilocytic astrocytoma, World Health Organization grade 1. The patient returned to her baseline function after several weeks and the imaging remained stable at the 4-month follow-up. CONCLUSIONS: Spinal pilocytic astrocytomas constitute 90% of intramedullary spinal cord tumors in patients younger than 10 years and 60% of those in adolescent patients. There are very few reported cases in patients older than 50 years. Our patient had an indolent course, cervical-thoracic location, imaging characteristics, and pathology that all support a diagnosis of pilocytic astrocytoma. This case highlights that low-grade lesions can occur in elderly patients and an aggressive approach may not be indicated.