Radiation-induced neoplasms of the brain

Abstract
The histopathology of two patients with radiation‐induced neoplasms of the brain following therapeutic irradiation for intracranial malignancies is described. The second neoplasms were an atypical meningioma and a polymorphous cell sarcoma, respectively. They occurred 12 and 23 years after irradiation (4000 rad), within the original field of irradiation. In both cases, the radiation‐induced tumors were histologically distinct from the initial medulloblastomas. Both patients were retreated with local irradiation using permanent implantation of radioactive iodine‐125 seeds.