have been reported. Increasing age (> 60 years) carries a worse prognostic risk. Death is usually due to widespread tumor infiltration with cerebral edema and increased intracranial pressure. A good initial Karnofsky performance score (KPS) and MGMT methylation are associated with longer survival. A DNA test can be conducted on glioblastomas to determine whether or not the promoter of the MGMT gene is methylated. Patients with a methylated MGMT promoter have longer survival than those with an unmethylated MGMT promoter, due in part to increased sensitivity to temozolomide. Another positive prognostic marker for glioblastoma patients is mutation of the IDH1 gene, which can be tested by DNA-based methods or by immunohistochemistry using an antibody against the most common mutation, namely IDH1-R132H. More prognostic power can be obtained by combining the mutational status of IDH1 and the methylation status of MGMT into a two-gene predictor. Patients with both IDH1 mutations and MGMT methylation have the longest survival, patients with an IDH1 mutation or MGMT methylation an intermediate survival, and patients without either genetic event have the shortest survival. Long-term benefits have also been associated with those patients who receive surgery, radiotherapy, and temozolomide chemotherapy. However, much remains unknown about why some patients survive longer with glioblastoma. Age under 50 is linked to longer survival in GBM, as is 98%+ resection and use of temozolomide chemotherapy and better KPSs. A recent study confirms that younger age is associated with a much better prognosis, with a small fraction of patients under 40 years of age achieving a population-based cure. Cure is thought to occur when a person's risk of death returns to that of the normal population, and in GBM, this is thought to occur after 10 years. UCLA Neuro-oncology publishes real-time survival data for patients with this diagnosis. According to a 2003 study, GBM prognosis can be divided into three subgroups dependent on KPS, the age of the patient, and treatment. Epidemiology About three per 100,000 people develop the disease a year, although regional frequency may be much higher. The frequency in England doubled between 1995 and 2015. It is the second-most common central nervous system cancer after meningioma. It occurs more commonly in males than females. Although the average age at diagnosis is 64, in 2014, the broad category of brain cancers was second only to leukemia in people in the United States under 20 years of age. History The term