Gefitinib Plus Temozolomide in Treating Patients With Malignant Primary Glioma

DISEASE CHARACTERISTICS: Histologically confirmed malignant primary glioma Glioblastoma multiforme Anaplastic astrocytoma Anaplastic oligodendroglioma Anaplastic mixed oligoastrocytoma Malignant astrocytoma not otherwise specified Stable or progressive disease Progressive disease after interstitial brachytherapy or stereotactic radiosurgery must be confirmed by positron emission tomography or thallium scan, magnetic resonance spectroscopy, or surgical biopsy Prior treatment for no more than 3 prior relapses allowed PATIENT CHARACTERISTICS: Age: 18 and over Performance status: Karnofsky 60-100% Life expectancy: More than 8 weeks Hematopoietic: WBC greater than 3,000/mm^3 Absolute neutrophil count greater than 1,500/mm^3 Platelet count greater than 120,000/mm^3 Hemoglobin greater than 10 g/dL (transfusion allowed) Hepatic: Bilirubin less than 1.5 times upper limit of normal (ULN) SGOT less than 1.5 times ULN Renal: Creatinine less than 1.5 mg/dL OR Creatinine clearance greater than 60 mL/min Other: Not pregnant Negative pregnancy test Fertile patients must use effective contraception No active infection No other concurrent significant medical illness that would preclude study participation No significant gastrointestinal risk factors (e.g., active ulcerative colitis) within the past 6 months No other malignancy within the past 3 years except non-melanoma skin cancer or carcinoma in situ of the cervix PRIOR CONCURRENT THERAPY: Biologic therapy: At least 1 week since prior interferon No concurrent filgrastim (G-CSF) during the first course of study therapy Chemotherapy: At least 2 weeks since prior vincristine At least 3 weeks since prior procarbazine At least 6 weeks since prior nitrosoureas Prior or concurrent temozolomide allowed if there is no evidence of progression while receiving therapy Endocrine therapy: At least 1 week since prior tamoxifen Must be on a stable dose of corticosteroids for at least 5 days Radiotherapy: See Disease Characteristics At least 3 weeks since prior radiotherapy Surgery: See Disease Characteristics At least 1 week since prior surgical resection Other: Recovered from all prior therapy No prior gefitinib At least 1 week since prior non-cytotoxic agents except radiosensitizers At least 4 weeks since prior cytotoxic therapy At least 4 weeks since prior investigational agents At least 3 years since prior therapy for other malignancy Concurrent therapeutic agents allowed at stable dosage Concurrent enzyme-inducing anti-epileptic drugs allowed if continued during study participation