Radiation necrosis, a focal structural lesion that usually occurs at the original tumor site, is a potential long-term central nervous system (CNS) complication of radiotherapy or radiosurgery. Edema and the presence of tumor render the CNS parenchyma in the tumor bed more susceptible to radiation necrosis. Radiation necrosis can occur when radiotherapy is used to treat primary CNS tumors, metastatic disease, or head and neck malignancies. It can occur secondary to any form of radiotherapy modality or regimen.

Radiation necrosis can present with signs of mass effect, elevated intracranial pressure, obstructive hydrocephalus, herniation syndromes, seizures, hemorrhage, cognitive and personality changes.

Treatment
Surgical decompression of any radionecrosis-related mass effect can provide helpful palliative effect. Corticosteroids usually produce prompt symptomatic improvement, and symptoms of cerebral edema can resolve with conservative management.

See reference for details.

Adapted from Medscape Drugs & Diseases. Radiation necrosis. Available at http://emedicine.medscape.com/article/1157533-overview. Accessed February 15, 2016. To view the entire article and all other content on the Medscape Drugs & Diseases site, a free, one-time registration is required.