Mycophenolate Mofetil in Combination With Standard of Care for the Treatment of Glioblastoma

Inclusion Criteria: * GROUPS 1-3: Histologically confirmed glioblastoma (GBM), IDH wild-type (by immunohistochemistry \[IHC\] R132H negative \[neg\] or sequencing). Astrocytoma with molecular features of GBM are eligible. * GROUPS 1-3: Newly diagnosed glioblastoma and: * Group 1: Received surgical resection or biopsy followed by chemoradiation; * Group 2: Received surgical resection or biopsy only and have documented unmethylated glioblastoma (may have been done at an outside facility); * Group 3: Received surgical resection or biopsy only * GROUP S: Newly suspected glioblastoma or recurrent glioblastoma, and scheduled to undergo a standard of care surgical resection or biopsy. * Stable or decreasing dose of corticosteroids equivalent to =\< 8 mg dexamethasone daily, for \>= 7 days prior to registration. * Note: There are no restrictions on steroid use on study * Patients must be age \>= 18 years. * Patients must exhibit a Karnofsky performance status \>= 70. * Leukocytes (white blood cells \[WBC\]) \>= 3,000/mcL (within 14 days prior to study registration) * Absolute neutrophil count (ANC) \>= 1,500/mcL (within 14 days prior to study registration) * Hemoglobin (Hgb) \>= 8 g/dL (within 14 days prior to study registration) (transfusion may be used for eligibility if \>= 7 days) * Platelets (PLT) \>= 100,000/mcL (within 14 days prior to study registration) (transfusion or growth factor may be used for eligibility if \>= 7 days). * Total bilirubin =\< 2x institutional…