Fig. 1

A 54 years-old female patient with extensive edema on T2 MRI (a) and new contrast enhancing lesions at the temporal and occipital lobe (b) after undergoing stereotactic radiosurgery for brain metastases from malignant melanoma at both sites. MRI findings were suggestive for tumor recurrence, whereas only a faint uptake on ¹⁸F-FET PET (c) and fused PET/MRI (d) was seen in both lesions, a finding typical for radiation necrosis. Radiation necrosis was subsequently confirmed by histopathology