Celecoxib in Patients With Newly Diagnosed GBM Who Are Receiving Anticonvulsant Drugs and Undergoing RT

DISEASE CHARACTERISTICS: Histologically confirmed glioblastoma multiforme Supratentorial Grade IV astrocytoma PATIENT CHARACTERISTICS: Age 18 and over Performance status Karnofsky 60-100% Life expectancy Not specified Hematopoietic Absolute neutrophil count at least 1,500/mm^3 Platelet count at least 100,000/mm^3 Hemoglobin at least 9.0 g/dL Hepatic Bilirubin no greater than 1.5 mg/dL Transaminases no greater than 4 times upper limit of normal Renal Creatinine no greater than 1.7 mg/dL Creatinine clearance at least 60 mL/min No prior renal toxicity with nonsteroidal anti-inflammatory drugs Other Not pregnant or nursing Negative pregnancy test Fertile patients must use effective contraception Mini mental score at least 15 No history of peptic disease No serious concurrent infection No other medical illness that would preclude study participation No other malignancy within the past 5 years except curatively treated carcinoma in situ or basal cell skin cancer No allergy to sulfonamides Able to tolerate cyclo-oxygenase-2 (COX-2) inhibitors PRIOR CONCURRENT THERAPY: Biologic therapy No prior immunotherapy or biologic agents for the malignancy, including any of the following: Immunotoxins Immunoconjugates Antisense agents Peptide receptor antagonists Interferons Interleukins Tumor-infiltrating lymphocytes Lymphokine-activated killer cells Gene therapy No concurrent prophylactic growth factors (e.g., filgrastim [G-CSF] or sargramostim [GM-CSF]) Chemotherapy No prior chemotherapy for the malignancy Endocrine therapy No prior hormonal therapy for the malignancy Prior glucocorticoid therapy allowed Concurrent corticosteroids allowed provided there has been no dose increase within the past 5 days Radiotherapy No prior radiotherapy for the malignancy Surgery Recovered from prior surgery Other At least 1 week since prior fluconazole More than 10 days since prior anticonvulsant drugs that induce hepatic metabolic enzymes (Group A) No other prior therapy for the malignancy No concurrent enrollment in another therapeutic clinical trial No concurrent fluconazole