Radiation necrosis of the brain in patients receiving radiation therapy for tumors. Pathophysiology, diagnosis and treatment

Summary One of the most serious complications of radiotherapy of brain tumors is the necrosis in the irradiated area. Prediction of necrosis development, understanding of the pathogenesis, timely diagnosis and adequate treatment will reduce the risk and provide the necessary medical care. In this regard, we analyzed literature data on radiation necrosis (RN) using MEDLINE database. The risk of RN increases with the increase of fraction magnitude, total doses and volumes of irradiation, with the addition of chemotherapy and immunotherapy, with repeated courses of radiation therapy. In the pathogenesis of RN, the main role belongs to capillary wall damage because of overproduction of vascular endothelial growth factor (VEGF) with the development of tissue edema, ischemia and inflammation due to cytokine release. Differential diagnosis of RN from tumor growth resumption is carried out using magnetic resonance imaging techniques (MR- spectroscopy and diffusion weighted imaging, perfusion MRI), as well as positron emission tomography with methionine as a carrier. The most effective treatment for RN is the surgical removal of the affected area. However, since surgery is possible for a small number of patients, the main method of treatment is conservative therapy aimed at reducing VEGF production, edema and 3 inflammation. For this purpose corticosteroid hormones, antiangiogenic factors and diuretics are used.