Combined pleomorphic xanthoastrocytoma-ganglioglioma of the cerebellum.

Combined pleomorphic xanthoastrocytoma-ganglioma is a rare neoplasm, occurring in patients younger than 30 years. The clinical course of these tumors is difficult to predict because of their rarity. We report a case of combined pleomorphic xanthoastrocytoma-ganglioma that, in addition to the patient's age, is unusual in several respects. The lesion was located in the cerebellar vermis of a 60-year-old man and was radiographically solid. Histologically, there was an admixture of markedly pleomorphic astrocytic cells and neoplastic ganglion cells, with permeation of the overlying leptomeninges and surrounding cerebellum. In addition, there was focal capillary endothelial proliferation. There was no necrosis, and mitotic activity was rare at 1 mitotic figure per 40 high-power fields. The patient underwent a near gross total resection and postoperative radiotherapy and remains well through 16 months of follow-up.