Radiation Therapy With Concomitant and Adjuvant Temozolomide Versus Radiation Therapy With Adjuvant PCV Chemotherapy in Patients With Anaplastic Glioma or Low Grade Glioma

Pre-Registration Inclusion Criteria: * United States (US) and Canadian sites: \* This review is mandatory prior to registration to confirm eligibility; patients must be willing to submit tissue samples for mandatory central pathology review submission; it should be initiated as soon after surgery as possible * Tissue must have been determined to have local 1p/9q co-deletion and IDH mutation prior to submission for central path review * Tumor tissue must show co-deletion of chromosomes 1p and 19q; for eligibility, the 1p/19q analysis results will be accepted from the local site, as determined by either a locally available or reference laboratory (for US, must be Clinical Laboratory Improvement Act \[CLIA\] certified); acceptable methods for determination of 1p/19q loss include fluorescent in-situ hybridization (FISH), by genomic sequencing or methylomic analyses; US and Canadian sites must send a copy of the official report to the pathology coordinator and quality assurance specialist (QAS) * Tumor must also show evidence of IDH mutation by immunohistochemistry or genomic analyses; this should be performed at the local site (US: performed in a CLIA certified laboratory); the site must send a copy of the official report to the pathology coordinator and QAS Registration Inclusion Criteria: * Newly diagnosed and =\< 3 months from surgical diagnosis; patients are also eligible if they have had a prior surgical procedure \> 3 months earlier for low grade glioma, as long …