Temozolomide, Thalidomide, and Celecoxib Following Radiation Therapy in Treating Patients With Newly Diagnosed Glioblastoma Multiforme

RATIONALE: Drugs used in chemotherapy use different ways to stop tumor cells from dividing so they stop growing or die. Thalidomide and celecoxib may stop the growth of tumor cells by stopping blood flow to the tumor and may increase the effectiveness of temozolomide by making tumor cells more sensitive to the drug. PURPOSE: Phase II trial to study the effectiveness of combining temozolomide, thalidomide, and celecoxib following radiation therapy in treating patients who have newly diagnosed glioblastoma multiforme.