This study does not add any additional treatment to patients with malignant glioma who are already scheduled to receive bevacizumab monotherapy. All treatment decisions will be at the discretion of the treating physician. There will be no change in the diagnosis or management of the patient based on any procedures or tests carried out as a part of this study.
If the participant chooses to take part in this research study each treatment cycle will last 28 days.
* Day 1-The participant will have the following procedures done before they can receive bevacizumab:
* An assessment of the participant's tumor by Vascular MRI (Magnetic Resonance Imaging) and FMISO-PET scans
* Blood pregnancy test for women of childbearing potential.
* Day 14:The participant will have the following procedures done after they receive bevacizumab:
* An assessment of the participant's tumor by Vascular MRI (Magnetic Resonance Imaging) and FMISO-PET scans before the participant have received bevacizumab
* Blood pregnancy test for women of childbearing potential.
* Day 28: The participant will have the following procedures done after they receive bevacizumab:
* An assessment of the participant's tumor by Vascular MRI (Magnetic Resonance Imaging) and FMISO-PET scans after the participant has received bevacizumab
* Blood pregnancy test for women of childbearing potential.
FMISO-PET Scans:
* The participant will have the scans performed in Charlestown, MA at the Martinos Center. The participant will be injected with two separate intravenous (IV) injections (listed below). Intravenous means a need will be injected into a vein in the participant's arm.
* FMISO for PET scan and a contrast dye for the MRI scan
* Drawing blood to assess the radioactivity of FMISO
* The PET scan will take approximately 60-75 minutes. The participant will receive one injection of FMISO. Following the injection of the radiotracer, blood samples will be taken from the second IV line. The tracer is given through a vein (IV) and travels through the participant's blood and collects in organs and tissues. The participant will need to wait nearby as the tracer is absorbed by the their body. This takes about 90 minutes. Then, the participant will lie on a narrow table that slides into a large tunnel-shaped scanner. The PET will pick up signals from the tracer and a computer will change the signals into 3D pictures that will be displayed on a monitor for the participant's study doctor to read.
MRI Scan:
* MRI scans will last about 60-75 minutes. This will occur at the same time as the PET scan. The participant will be injected with contrast dye twice during the MRI scan. The participant will have 3 MRI scans (prior to starting treatment, day 1 of treatment and day 14 of treatment) that would not have routinely been performed if the participant were not participating in this study.
* Blood samples will be collected during both scans in order to measure how the participant blood vessels are processing the radiotracer FMISO and how well it is being delivered to the tumor tissue.
* The participant will be assessed for side effects via clinic visit or phone call about 24 hours after each of the visits above.
Planned Follow-up: The investigators would like to call the participant every 3 months for three years after the 28 day visit to see how they are doing and if the participant is experiencing any side effects. If the participant is removed from the study due to an unacceptable side effect, the participant will be followed until it has been resolved.
