Primary Objectives:To perform metabolic phenotyping of treatment naïve and recurrent GBM by multitracer [18F]Fluciclovine and 18F-FDG PET. Secondary Objectives:To compare uptake measures of 18F-Fluciclovine and 18F-FDG and MRI quantification of glutamate and lactate levels to tumor tissue laboratory assays (RNA seq and proteomics) of glutamine/glutamate, glucose, and lactate metabolism. To …