Imatinib Mesylate and Temozolomide in Treating Patients With Malignant Glioma

DISEASE CHARACTERISTICS: * Histologically confirmed malignant glioma * Any of the following subtypes: * Glioblastoma multiforme * Gliosarcoma * Anaplastic astrocytoma * Anaplastic oligodendroglioma * Anaplastic oligoastrocytoma * Previous histologic diagnosis of a lower grade of glioma allowed if there is histologic evidence of progression to a diagnosis of malignant glioma * Multifocal disease allowed * Must have undergone prior conventional external-beam radiation therapy * Stable disease, disease recurrence, or relapsed disease * Must not have received any systemic therapy for this recurrence or relapse * No prior progressive disease * No central/systemic fluid collections (pericardial effusion, pulmonary effusion, ascites) ≥ grade 2 * No evidence of intratumor hemorrhage on pretreatment diagnostic imaging, except for stable post-operative grade 1 hemorrhage PATIENT CHARACTERISTICS: * Karnofsky performance status 70-100% * Absolute neutrophil count \> 1,500/mm³ * Hemoglobin \> 9 g/dL * Platelet count \> 100,000/mm³ * AST and ALT \< 2.5 times upper limit of normal (ULN) * Bilirubin \< 1.5 times ULN * Creatinine \< 1.5 times ULN * No chronic renal disease * No active uncontrolled infection * No uncontrolled diabetes * No excessive risk of bleeding, as defined by occurrence of any of the following: * Stroke within the past 6 months * History of CNS or intraocular bleed * Septic endocarditis * No history of labile hypertension * No congestive heart failure * No poorly controlled hypertension * No myocardial infarction within the past 6 months * No history of poor compliance with antihypertensive regimen * No other severe and/or uncontrolled medical disease that would preclude study participation * No peripheral edema ≥ grade 2 * No gastrointestinal bleeding * No gross hematuria * No other active systemic bleeding * Patients must not have experienced toxicity ≥ grade 3 with prior treatment with either temozolomide or imatinib mesylate * No other primary malignancy within the past 5 years except basal cell skin cancer or carcinoma in situ of the cervix or other cancer not currently clinically significant nor requiring active interventions PRIOR CONCURRENT THERAPY: * See Disease Characteristics * Recovered from all prior therapy * Prior surgical resection(s) allowed * At least 2 weeks since prior surgery * At least 2 weeks since prior chemotherapy (6 weeks for nitrosoureas) * At least 2 weeks since prior external-beam radiotherapy * At least 2 weeks since prior investigational drugs * More than 1 week since prior biologic, immunotherapeutic, or cytostatic agents * No concurrent warfarin