Inclusion Criteria:

- Newly diagnosed or suspected high grade glioma ≥ 1cm in diameter on postoperative
anatomic imaging (contrast MRI), prior to initiation of chemoXRT

- Anticipated survival ≥6 months

- Able to give informed consent

- Capable of undergoing MRI and PET scans without the need for sedation or general
anesthesia

- Male or Female

Exclusion Criteria:

- Prior radiation therapy and chemotherapy to the brain

- Active intracranial infection or nonglial brain mass.

- Recent large intracranial hemorrhage (<1 month)

- Expected survival <6 months

- Pregnant or nursing

- Renal failure

- Lives far from BWH and/or is unwilling/ unable to return for scheduled imaging
visits.