LAUSR

A 75-year-old man with a 6-year history of left auditory neuroma was referred for a follow up MRI scan. The MRI scan revealed a known stable neuroma and a 42 × 42 × 58mm abnormal focal lesion in the right parietal lobe, showing an increased signal on T2-weighted fat-saturated images, and marked nonhomogeneous contrast enhancement on T1weighted gradient-echo images. The radiologist suggested glioblastoma multiforme (GBM). The patient reported a 6week history of walking difficulty. For tumour biology status, the patient was referred to the Nuclear Medicine Department. PET/CT with Ga-PSMA was performed. The whole-body Ga-PSMA image (a) shows increased uptake in the right parietal mass. The Ga-PSMA PET/CT images (b–d) show nonhomogeneous uptake in the right parietal mass (b SUVmax 23.7), lower uptake in the left auditory neuroma (c SUVmax 5.0), as well as a small focus in the prostate gland (d SUV max 9.5). For characterization of the brain lesion, F-FDG PET/CT was additionally performed (e–g), and showed increased uptake comparable to that in the grey matter in the parietal tumour (e SUVmax 13.4), no uptake in the neuroma (f) and no uptake in the prostate gland (g).