Despite maximum treatment, the cancer usually recurs. The typical duration of survival following diagnosis is 12 to 15 months, with fewer than 3 to 7% of people surviving longer than five years. Without treatment, survival is typically three months. It is the most common cancer that begins within the brain and the second-most common brain tumor, after meningioma. About 3 in 100,000 people develop the disease per year. It most often begins around 64 years of age and occurs more commonly in males than females. Immunotherapy is being studied as treatment for the cancer.