Diencephalic juvenile pilomyxoid astrocytoma with leptomeningeal dissemination.

Pilomyxoid astrocytoma (PMA) is a recently described neoplasm. PMA shares few features with pilocytic astrocytoma (PA), the most common central nervous system (CNS) tumor in the pediatric population, yet displays histological differences. Previous studies have shown that PMAs have more aggressive biological behavior as compared to PA. These findings suggest that PMA may be a unique and distinct neoplasm. We report a pilomyxoid astrocytoma of the hypothalamic-chiasmatic region with leptomeningeal dissemination in a 3-month old infant. This case report discusses the histological, clinical, and radiographic characteristics of PMA. In addition, the current treatment options and research potential involving this disease are also briefly described.