Arsenic Trioxide and Radiation Therapy in Treating Young Patients With Newly Diagnosed Gliomas

RATIONALE: Drugs used in chemotherapy, such as arsenic trioxide, work in different ways to stop tumor cells from dividing so they stop growing or die. Radiation therapy uses high-energy x-rays to damage tumor cells and may be an effective treatment for patients with glioma. Drugs such as arsenic trioxide may also make the tumor cells more sensitive to radiation therapy. Combining arsenic trioxide with radiation therapy may kill more tumor cells. PURPOSE: Phase I trial to study the effectiveness of combining arsenic trioxide with radiation therapy in treating patients who have newly diagnosed gliomas.