Radiation-induced schwannomas of the nervous system. Report of five cases and review of the literature.

Radiation therapy has important delayed effects on the central nervous system. Prominent among these effects is radiation necrosis of nervous tissue, but an oncogenic effect is also recognized. Both benign and malignant intracranial tumors can develop in irradiated fields, particularly in children. Most of these tumors are sarcomas, meningiomas or gliomas and only occasionally schwannomas. We report 5 cases of postirradiation acoustic nerve schwannoma observed in our Department.