Advances in the prevention and treatment of radiation-induced brain necrosis: a narrative review

Radiation-induced brain necrosis (RBN) is a serious and often debilitating complication of radiotherapy for intracranial and head and neck malignancies, with an incidence of 5–25%. It can lead to significant cognitive impairment, neurological deficits, and increased mortality. As radiotherapy techniques advance and patient survival improves, effective prevention and management of RBN have become critical clinical priorities. This review systematically summarizes the current understanding of RBN pathogenesis, highlighting the central roles of vascular injury (endothelial damage, HIF-1α/VEGF dysregulation) and neuroinflammation (microglial activation, cytokine release). We discuss recent advances in preventive strategies, including refined radiotherapy modalities such as intensity-modulated radiotherapy (IMRT), fractionated stereotactic radiosurgery (fSRS), and FLASH ultra-high-dose-rate radiotherapy, as well as pharmacological prophylaxis using bevacizumab and neuroprotective agents (NGF, GM1, edaravone). Established and emerging treatment options are reviewed, including corticosteroids, bevacizumab, hyperbaric oxygen therapy (HBOT), laser interstitial thermal therapy (LITT), and Colony Stimulating Factor 1 Receptor(CSF1R) inhibitors. We also cover innovations in imaging for early detection and differential diagnosis, including magnetic resonance spectroscopy (MRS), perfusion-weighted imaging (PWI), and Positron Emission Tomography-Computed Tomography(PET/CT) with advanced tracers ( 11 C-methionine, 18 F-FET). Finally, we summarize updates to international management guidelines, particularly the 2022 DEGRO guidelines, and propose future directions for research and therapeutic optimization.