Postirradiation meningioma.

A case of meningioma of the posterior cranial fossa is reported. The tumor developed 12 years after radiation treatment for a polar spongioblastoma of the cerebellum in an 8-year-old boy. The possible role of the radiation in the oncogenesis of the second tumor is discussed. In light of the information in the literature concerning the malignancy of such postirradiation tumors, the authors recommend careful evaluation for the real necessity of radiation therapy, particularly for children in whom the meninges may be hypersensitive to ionizing radiation.