Tumor Treating Fields With Chemoradiation in Newly Diagnosed GBM

Inclusion Criteria: 1. GBM or Gliosarcoma by histology 2. MGMT methylation status and IDH mutation status must be assessed at the study site or patient's referral center. MGMT status will be used for stratification purposes but will not exclude patients from this study if they are either methylated, unmethylated, or indeterminate, or in process at the time of enrollment. Similarly, subjects with tumors that are IDH mutated or wild type are both eligible. 3. Supratentorial location 4. Maximum safe resection (including patients who can only safely be biopsied) 5. 22 years of age or older 6. Estimated survival of at least 12 weeks 7. KPS 70% or greater at time of entry to study 8. Patient provided written informed consent, or provided by a legally authorized representative 9. Willingness to comply with all procedures, including visits or evaluations, imaging, laboratory tests and rescue measures 10. Acceptable method of birth control (see appendix) 11. Have had a contrast-enhanced brain MRI after tumor resection procedure. If biopsy alone performed, cranial CT may be used in place of MRI, only if the patient had a preoperative MRI scan within 14 days of the biopsy. 12. The following time period must have elapsed prior to study enrollment: 3-6 weeks (21-42 days) from time of definitive surgery or 2-4 weeks (14-28 days) from the time of biopsy, for those who were only able to safely have a biopsy and not full resection. Exclusion Criteria: 1. Craniotomy or stereotactic biopsy wound dehiscence or infection 2. Known by history to be HIV positive or to have an AIDS-related illness, active Hepatitis B, or active Hepatitis C (testing not required) 3. Presence of skull defects (bullets, metal fragments, missing bone) 4. Patients with implanted electronic medical devices (including but not limited to: pacemaker, vagal nerve stimulator, or pain stimulator) 5. Prior invasive malignancy, unless disease free for 3 or more years, with the exception of basal cell carcinoma, cervical carcinoma in situ, or melanoma in situ 6. Recurrent malignant gliomas or higher grade gliomas transformed from previous low grade (II) glioma 7. Patients with any current Primary brain stem or spinal cord tumor 8. Prior use of temozolomide 9. Prior treatment with Avastin 10. Individuals requiring \>8mg of dexamethasone per day within 7 days prior to Day 1 (high dose steroid taper following craniotomy with \>8mg of dexamethasone is allowed during the screening period, but subjects must taper down to 8mg or less of dexamethasone (or bioequivalent) within 7 days prior to Day 1). 11. Clinically significant lab abnormalities at screening showing bone marrow, hepatic, and renal dysfunction: * Thrombocytopenia (platelet count \< 100 x 103/μL) * Neutropenia (absolute neutrophil count \< 1.5 x 103/μL) * Significant liver function impairment - AST or ALT \> 3 times the upper limit of normal * Total bilirubin \> upper limit of normal * Significant renal impairment (serum creatinine \> 1.7 mg/dL) 12. CTC grade 4 non-hematological Toxicity (except for alopecia, nausea, vomiting) at screening 13. Inability to swallow pills 14. Clinically significant or unstable comorbid medical condition, per investigator discretion (for example, active or uncontrolled infection requiring systemic therapy, including known HIV or hepatitis B or C virus) 15. Known current alcohol or drug abuse, per investigator discretion. Prior history of substance abuse is permissible if subject has been sober for the past 3 years. 16. Any clinically significant psychiatric condition that would prohibit patient willingness or ability to successfully complete study procedures, per investigator discretion 17. Patients with an allergy to or an inability to have gadolinium contrast dye administered with MRI 18. Patients with aneurysm clips or implanted metal objects in the brain 19. Patients with significant skin breakdown on the scalp 20. Patients who cannot receive standard of care radiation therapy and can only receive hypofractionated radiation due to age and poor performance status , per investigator discretion