TY - JOUR T1 - Although Non-diagnostic Between Necrosis and Recurrence, FDG PET/CT Assists Management of Brain Tumours After Radiosurgery JF - In Vivo JO - In Vivo SP - 513 LP - 520 VL - 30 IS - 4 AU - MICHAEL TORRENS AU - JULIA MALAMITSI AU - PANTELIS KARAISKOS AU - VARVARA VALOTASSIOU AU - FOTIS LASPAS AU - JOHN ANDREOU AU - CHRISTOS STERGIOU AU - VASSILIS PRASSOPOULOS Y1 - 2016/07/01 UR - http://iv.iiarjournals.org/content/30/4/513.abstract N2 - Aim: To re-evaluate the role of 18F-fluoro-deoxy-D-glucose (FDG) positron emission tomography/ computer assisted tomography (PET/CT) co-registered with magnetic resonance imaging (MRI) in differentiating adverse radiation effect (ARE) from tumour recurrence after Gamma Knife radiosurgery of brain tumours. Patients and Methods: Twenty-seven PET/CT studies co-registered with MRI were performed on 16 patients after radiosurgery, with 12/16 patients having multiple radiosurgery treatments. Long term follow-up was used for evaluation, with 3/16 patients being histopathologically confirmed. Results: PET/CT was positive in all studies in 6/16 patients, negative in all studies in 6/16 and changed from negative to positive in one. In 2/16 patients, PET/CT was both positive and negative in separate tumour foci. In 9/16 cases with a positive PET/CT, tumour was confirmed. In 6/16 patients with a negative PET/CT, 3/6 had recurrence and 3/6 ARE. In 1/16, equivocal results became negative after retreatment. PET/CT/MRI identified tumour within ARE. Sensitivity of PET/CT/MRI proved to be 64.7%, and specificity 100%. Conclusion: PET/CT/MRI assists management, by revealing metabolism rather than histology. ER -