Radiation therapy uses high-energy x-rays to kill tumor cells. Drugs used in chemotherapy, such as temozolomide, work in different ways to stop the growth of tumor cells, either by killing the cells or by stopping them from dividing. At the time of writing this protocol it was not known whether radiation therapy was more effective than temozolomide in treating gliomas. The purpose if this randomized phase III trial was to study radiation therapy to see how well it works compared to temozolomide in treating patients with gliomas.