Proton Beam or Intensity-Modulated Radiation Therapy in Preserving Brain Function in Patients With IDH Mutant Grade II or III Glioma

Inclusion Criteria:

* PRIOR TO STEP 1 REGISTRATION
* Tumor tissue must be available for submission for central pathology review
* Grade II and III gliomas IDH mutant gliomas including; diffuse astrocytoma, anaplastic astrocytoma, oligodendroglioma, anaplastic oligodendroglioma, oligoastrocytoma, anaplastic oligoastrocytoma
* Documentation from the enrolling site confirming the presence of IDH mutation and 1p/19q status; the provided information must document assays performed in clinical laboratory improvement amendments (CLIA)-approved laboratories and be uploaded prior to Step 2 registration
* Age \>= 18
* The trial is open to both genders
* Only English or French speaking patients are eligible to participate as the cognitive assessments are only available in these languages
* The patient or a legally authorized representative must provide study-specific informed consent prior to study entry
* History and physical exam, and Karnofsky performance status of \>= 70 within 30 days prior to registration
* Absolute neutrophil count (ANC) \>= 1,500 cells/mm\^3 (within 60 days prior to registration)
* Platelets \>= 100,000 cells/mm\^3 (within 60 days prior to registration)
* Hemoglobin \>= 10.0 g/dl (Note: the use of transfusion or other intervention to achieve hemoglobin \[Hgb\] \>= 10.0 g/dl is acceptable) (within 60 days prior to registration)
* Bilirubin =\< 1.5 upper limit of normal (ULN) (within 60 days prior to registration)
* Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) =\< 3 x ULN (within 60 days prior to registration)
* Blood urea nitrogen (BUN) \< 30 mg/dl (within 60 days prior to registration)
* Serum creatinine \< 1.5 mg/dl (within 60 days prior to registration)
* Pre-operative MRI imaging of the brain available for radiation planning
* Post-operative MRI imaging with contrast is mandatory obtained for radiation therapy planning; enrolling sites are not mandated although highly encouraged to obtain thin-slice (\< 1.5 mm) 3 dimensional (D) pre and post contrast and axial T2/FLAIR sequences for planning purposes
* Patients must be able to swallow capsules
* PRIOR TO STEP 2 REGISTRATION
* Histologically proven diagnosis of supratentorial, World Health Organization (WHO) grade II or III astrocytoma, oligodendroglioma or oligoastrocytoma, with IDH mutation confirmed by central review
* The following baseline neurocognitive assessments must be completed and uploaded prior to Step 2 registration: HVLT-R (recall, delayed recall, and recognition), TMT Parts A and B, and COWA; the neurocognitive assessment will be uploaded into a folder in the NRG Medidata RAVE System for central evaluation; once the upload and scoring of the tools are complete, a notification will be sent within 3 business days to the Research Associate (RA) to proceed to Step 2; in order for the patient to be eligible, at least 5 of the 6 neurocognitive assessments must be able to be scored (i.e. free of any errors)
* Completion of all items on the following baseline quality of life forms: MDASI-BT, LASA QOL, WPAI-GH and Employment Questionnaire; these quality of life forms will be required and data entered at step 2 registration
* Financial clearance for proton therapy treatment prior step 2 registration
* Women of childbearing age must have a negative serum pregnancy test within 14 days prior to step 2 registration

Exclusion Criteria:

* Definitive clinical or radiologic evidence of metastatic disease; if applicable
* Prior invasive malignancy (except non-melanomatous skin cancer) unless disease free for a minimum of 3 years; (for example, carcinoma in situ of the breast, oral cavity or cervix are permissible)
* Prior cranial radiotherapy or radiotherapy to the head and neck where potential field overlaps would exist
* Prior chemotherapy or radiotherapy for any brain tumor
* Histologic diagnosis of glioblastoma (WHO grade IV) or pilocytic astrocytoma (WHO grade I)
* Definitive evidence of multifocal disease
* Planned use of cytotoxic chemotherapy during radiation (only adjuvant temozolomide therapy will be used on this protocol)
* Patients with infra-tentorial tumors are not eligible
* Prior history of neurologic or psychiatric disease believed to impact cognitive function
* The use of memantine during or following radiation is NOT allowed
* Severe, active co-morbidity defined as follows:

  * Unstable angina or congestive heart failure requiring hospitalization within 6 months prior to enrollment
  * Transmural myocardial infarction within the last 6 months prior to registration; evidence of recent myocardial infarction or ischemia by the findings of S-T elevations of \>= 2 mm using the analysis of an electrocardiogram (EKG) performed within 28 days prior to registration (Note: EKG to be performed only if clinical suspicion of cardiac issue)
  * New York Heart Association grade II or greater congestive heart failure requiring hospitalization within 12 months prior to registration
  * Serious and inadequately controlled arrhythmia at step 2 registration
  * Serious or non-healing wound, ulcer or bone fracture or history of abdominal fistula, intra-abdominal abscess requiring major surgical procedure, open biopsy or significant traumatic injury within 28 days prior to registration, with the exception of the craniotomy for surgical resection
  * Acute bacterial or fungal infection requiring intravenous antibiotics at the time of registration
  * Hepatic insufficiency resulting in clinical jaundice and/or coagulation defects; note, however, that laboratory tests for coagulation parameters are not required for entry into this protocol
  * Chronic obstructive pulmonary disease exacerbation or other respiratory illness requiring hospitalization or precluding study therapy at the time of registration
  * Human immunodeficiency virus (HIV) positive with CD4 count \< 200 cells/microliter; acquired immune deficiency syndrome (AIDS) based upon current Centers for Disease Control and Prevention (CDC) definition; note, however, that HIV testing is not required for entry into this protocol
  * Any other severe immunocompromised condition
  * Active connective tissue disorders, such as lupus or scleroderma, that in the opinion of the treating physician may put the patient at high risk for radiation toxicity
  * End-stage renal disease (i.e., on dialysis or dialysis has been recommended)
  * Any other major medical illnesses or psychiatric treatments that in the investigator's opinion will prevent administration or completion of protocol therapy
* Inability to undergo MRI with and without contrast (e.g. claustrophobia, non-MRI compatible implant or foreign body, gadolinium allergy or renal dysfunction preventing the patient from receiving gadolinium- institutional guidelines should be used to determine if patients are at risk for renal dysfunction); note that patients with severe claustrophobia are permitted on this study if they are willing and able to undergo MRI with adequate sedation or anesthesia
* Patients known to have hypersensitivity to dacarbazine (DTIC) are not eligible