Leptomeningeal dissemination of juvenile pilocytic astrocytoma: case report.

The authors report a case of leptomeningeal spinal metastasis of chiasmatic juvenile pilocytic astrocytoma. A 7-year-old boy underwent surgery and radiation therapy for a chiasmatic pilocytic astrocytoma. Three years later he experienced a syndrome of medullary compression. A lumbosacral intradural extra-axial tumor was discovered and subtotally excised. Pathologic examination revealed a metastasis of the chiasmatic tumor without any evidence of malignant transformation. Only five cases of leptomeningeal spinal dissemination of pilocytic astrocytoma have been previously reported. The authors review and discuss the clinical and pathologic features of these cases.