Conventional Versus Hypofractionated Radiotherapy With Temozolomide in Elderly Glioblastoma

Inclusion Criteria: * newly diagnosed glioblastoma according to the 2021 World Health Organization classification * interval of ≤4 weeks between pathological diagnosis and randomization * aged 70 years or older * gadolinium-enhanced MRI within 72 hours of surgery * known o6-methylguanine-DNA-methyltransferase promoter methylation status * Karnofsky performance score ≥60 * stable or decreasing dose of steroid (if necessary) * no history of brain radiotherapy * no history of any systemic chemotherapy * adequate hematological, renal and hepatic functions for temozolomide * able to start radiotherapy within 3 weeks from randomization Exclusion Criteria: * patients with spinal leptomeningeal carcinomatosis * history of cancer other than the followings: * carcinoma in situ of the cervix * completely excised non-melanoma skin cancer * cancers without any evidence of residual disease for 5 years or longer * patients with serious active infection or other serious underlying medical conditions * patients with psychological issues that cannot comply to the protocol * patients with known hypersensitivity to temozolomide or compounds with similar chemical composition to temozolomide * patients who are currently participating in other clinical trials