Magnetic resonance imaging of pilocytic astrocytomas in adults with histopathologic correlation: a report of six consecutive cases

Pilocytic astrocytoma is a WHO grade I tumor usually diagnosed in pediatric patients, and rarely encountered in the adult popula-tion. Therefore, available information about the magnetic resonance imaging characteristics of adult pilocytic astrocytoma is scarce. We report on the MRI features and corresponding histopathologic find-ings of six consecutive aPA cases diagnosed. The tumors were en-countered in both infra-and supratentorial compartments, and their MRI characteristics were quite heterogeneous. Features included the typical solid-cystic appearance located in the cerebellum as well as the relatively unusual multifocal and/or hemorrhagic features lo-cated intra-ventricularly. The aPA MRI characteristics are remarkably variable, and might mimic those of higher grade tumors in adult pa-tients.