• Radiation necrosis or tumor progression? A review of the radiographic modalities used in the diagnosis of cerebral radiation necrosis
• A phase III, multicenter, randomized controlled trial of preoperative versus postoperative stereotactic radiosurgery for patients with surgically resectable brain metastases
• VEGFR-TKI treatment for radiation-induced brain injury after gamma knife radiosurgery for brain metastases from renal cell carcinomas
• The impact of embolization on radiosurgery obliteration rates for brain arteriovenous malformations: a systematic review and meta-analysis
• Feasibility of linac-based fractionated stereotactic radiotherapy and stereotactic radiosurgery for patients with up to ten brain metastases
• A Multi-Disciplinary Approach to Diagnosis and Treatment of Radionecrosis in Malignant Gliomas and Cerebral Metastases
• Magnetic Resonance-Guided Laser Interstitial Thermal Therapy for Management of Low-Grade Gliomas and Radiation Necrosis: A Single-Institution Case Series
• Sensitizing brain metastases to stereotactic radiosurgery using hyperbaric oxygen: A proof-of-principle study

Unfortunately, symptomatic radiation necrosis is notoriously hard to diagnose and manage. The features of RN overlap considerably with tumor recurrence and misdiagnosing RN as tumor recurrence may lead to deleterious treatment which may cause detrimental effects on the patient ¹⁾

Differentiating radiation necrosis from tumor progression on standard magnetic resonance imaging (MRI) is often difficult and advanced imaging techniques may be needed to make an accurate diagnosis.

Mayo et al. performed a literature review addressing the radiographic modalities used in the diagnosis of radiation necrosis.

Differentiating radiation necrosis from tumor progression remains a diagnostic challenge and advanced imaging modalities are often required to make a definitive diagnosis. If diagnostic uncertainty remains following conventional imaging, a multi-modality diagnostic approach with perfusion MRI, magnetic resonance spectroscopy (MRS), positron emission tomography (PET), single photon emission spectroscopy (SPECT), and radiomics may be used to improve diagnosis.

Several imaging modalities exist to aid in the diagnosis of radiation necrosis. Future studies developing advanced imaging techniques are needed ²⁾.

Mangesius et al. provide the experience of a tertiary tumor center with this important issue in neurooncology and provide an institutional pathway for dealing with this problem ³⁾.

Radiation necrosis differential diagnosis.