Pilomyxoid astrocytoma of the spinal cord: Report of three cases

Pilomyxoid astrocytoma (PMA) is a recently described, rare, circumscribed glioma similar to pilocytic astrocytoma. Despite its circumscribed nature, PMA implies a worse overall outcome than typical pilocytic astrocytoma. All PMAs reported to date involved the hypothalamic/chiasmatic region. Since these original reports, we have encountered three tumors in the spinal cord with histological features identical to those of PMA. We report three male pediatric patients. The first patient presented at age 6 with back pain and constipation. The second patient presented at age 8 with back pain and a bout of urinary incontinence. The third patient, a neonate, presented with respiratory failure and hypotonia. The first patient's cervical and thoracic neoplasm was treated with subtotal resection and multiple laminectomies and spinal fusion for recurrence. The second patient underwent gross total resection of his thoracic neoplasm. The neonate underwent laminectomy and biopsy of his holocord tumor. PMAs typically occur in the hypothalamic region and within the first 4 years of life. Tumors with identical histological features are being recognized outside this typical clinical setting. The cases presented in this report suggest that PMA can occur at a later age and can involve the spinal cord. We believe that increased recognition of these circumscribed gliomas will help to elucidate their nature and lead to better management decisions.