Pleomorphic xanthoastrocytoma: a new differential diagnosis for a pediatric pineal neoplasm.

The pleomorphic xanthoastrocytoma (PXA) is an infrequently occurring benign astrocytic tumor with a predilection for the temporal and parietal cortices of children and young adults. We describe its occurrence in an unusual location in a 15-year-old boy who presented with raised intracranial pressure of short duration. Imaging showed a 3 × 3.2 × 3.5 cm mass in the pineal region extending into the quadrigeminal cistern. It had a contrast-enhancing solid component and a larger, ventrally located, peripherally enhancing cystic component. Total excision of the lesion was achieved via a modified left Poppen's approach. Histopathology and immunochemistry were suggestive of a PXA. This is the first report in the pediatric literature describing a PXA in the pineal region.