Feasibility of FMISO in Brain Tumors

Inclusion Criteria: * Adult patients (18 years of age and older) with a clinically suspected glioma * Able to provide informed written consent and/or acceptable surrogate capable of providing consent on the patient's behalf * Legally authorized representative (LAR)-signed informed consent and assent obtained for those subjects identified as decisionally impaired * Intracranial disease greater than 5 mL as assessed by T2/fluid attenuated inversion recovery (FLAIR) MR imaging * Karnofsky performance score \> 60 or Eastern Cooperative Oncology Group (ECOG) \< 3 as assessed by referring clinician. * Either has previously received therapeutic intervention for an intracranial tumor or is eligible for and agreeable to receiving standard of care stupp protocol radiation and temozolomide after biopsy or maximum safe surgical resection * Life expectancy of at least 6 months * Female subject of childbearing potential will be asked for possibility of pregnancy. If unsure of pregnancy status, then a negative urine or serum pregnancy within 72 hours prior to receiving the first dose of study drug (FMISO). If the urine test is positive or cannot be confirmed as negative, a serum pregnancy test will be required * Adequate organ function as demonstrated by a chart review of platelets, renal, hepatic, and coagulation. We will follow the Department of Diagnostic Radiology clinical policy for assessing renal function prior to injecting gadolinium-based contrast. If there is a history of poor kidney function, a point of care serum creatinine test may be performed to ensure adequate kidney function prior to FMISO administration. If there is a history of any other poor organ function, we will not administer Ferumoxytol, but the subject may receive all other study interventions Exclusion Criteria: * Pregnant or breastfeeding. * Contraindication to PET, MRI, FMISO, ferumoxytol, or intravenous gadolinium based contrast agents. * Claustrophobia is not controlled with medical therapy * Weight is greater than modality maximum capacity. * Presence of metallic foreign body or implanted medical devices in body not documented as MRI safe according to the Oregon Health \& Science University (OHSU) Department of Radiology guidelines (including but not limited to cardiac pacemaker, aneurysm clips, surgical clips, prostheses, artificial hearts, valves with steel parts, metal fragments, shrapnel, tattoos near the eye, or steel implants). * Subjects with family history of or known iron overload (genetic hemochromatosis). * Subject who have received ferumoxytol within 3 weeks of study entry and require another ferumoxytol administration. * Subjects with three or more drug allergies from separate drug classes. * History of hypersensitivity allergic reactions attributed to compounds of similar chemical or biologic composition to FMISO. An allergic reaction to nitroimidazoles is highly unlikely. * Sickle cell disease. * History of hypersensitivity allergic reactions attributed to compounds of similar chemical or biologic composition to ferumoxytol or gadolinium MRI contrast * Unsure of pregnancy status as assessed by Department of Radiology and AIRC guidelines. * Subjects for whom supplemental oxygen could be harmful such as people with potential for hypoventilation (end-stage chronic obstructive pulmonary disease \[COPD\], obstructive sleep apnea \[OSA\] on continuous positive airway pressure \[CPAP\]/biphasic positive airway pressure \[Bi-PAP\], etc). * Presence of any other co-existing condition that, in the judgment of the principal investigator, might increase the risk to the subject (i.e., plans for hospice or end of life care). * Poor peripheral intravenous access evaluated by patient history. * Presence of other serious systemic illnesses, including: uncontrolled infection, other uncontrolled malignancy, uncontrolled diabetes type II, or psychiatric/social situations which might impact the endpoint of the study or limit compliance with study requirements.