Approach to the patient with radiation necrosis

Early or delayed cerebral radiation necrosis can occur weeks or years after radiation therapy to the brain and can mimic the radiological appearance and the clinical course of a recurrent tumor. The risk of radiation necrosis may be dependent on radiation dose, fraction size, volume and location of brain irradiated, molecular features of the tumor, and concomitant systemic therapy. The diagnosis and management of radiation necrosis should involve multidisciplinary care. In the absence of surgical confirmation, diagnosis is typically made as a clinical diagnosis based on serial magnetic resonance imaging (MRI) and follow-up. Advanced imaging techniques such as MR perfusion, MR spectroscopy, or positron emission tomography (PET) may aid with the diagnosis but have not been extensively validated for their accuracy. Treatment options may include steroids, surgery, bevacizumab, hyperbaric oxygen, or interstitial laser ablation.