11C-methionine PET as a prognostic marker in patients with glioma: comparison with 18F-FDG PET

PURPOSE: The purpose of this study was to compare the prognostic value of 11C-methionine (MET) and 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET) in glioma patients. METHODS: The study population comprised 47 patients with gliomas (19 glioblastoma, 28 others). Pretreatment magnetic resonance imaging, MET PET and FDG PET were performed within a time interval of 2 weeks in all patients. The uptake ratio and standard uptake values were calculated. Univariate and multivariate analyses were done to determine significant prognostic factors. Ki-67 index was measured by immunohistochemical staining, and compared with FDG and MET uptake in glioma. RESULTS: Among the several clinicopathological prognostic factors, tumour pathology (glioblastoma or not), age (> or =60 or or =70 or