6 Months Adjuvant Temozolomide (TMZ) vs No Adjuvant TMZ in Newly Diagnosed MGMT Methylated Glioblastoma (GBM)

The primary objective of this trial is to evaluate overall survival of patients with O\[6\]-methylguanine-DNA methyltransferase (MGMT) methylated glioblastoma treated with or without six months of adjuvant TMZ after standard radiation (6000 centigray (cGy)) plus concurrent Temozolomide (TMZ). Secondary Objectives include to prospectively assess the overall adverse event profile in the two treatment arms. To compare lymphocyte counts overtime between the two treatment arms and to prospectively compare quality of life in the two treatment arms as assessed by MD Anderson Symptom Inventory-Brain Tumor Module (MDASI-BT) and Neurological quality of Life/minimal infecting dose (NeuroQoL) (MID). The study will also compare progression-free survival between the two treatment arms.