Hydroxyurea With or Without Imatinib Mesylate in Treating Patients With Recurrent or Progressive Meningioma

DISEASE CHARACTERISTICS: * Diagnosed with meningioma * WHO grade I-III * Recurrent or progressive disease after prior surgery and radiotherapy, or radiosurgery * Not amenable to further surgery * No optic nerve sheet tumor and neurofibromatosis type II * No known brain metastasis PATIENT CHARACTERISTICS: * WHO performance status 0-2 * ANC \> 1,500/mm\^3 * Platelet count \> 100,000/mm\^3 * Hemoglobin ≥ 9 mg/dL (transfusion allowed) * Total bilirubin \< 1.5 times upper limit of normal (ULN) * SGOT and SGPT \< 2.5 times ULN * Creatinine \< 1.5 times ULN * Negative pregnancy test * Fertile patients must use effective barrier method contraception during and for up to 3 months after completion of study therapy * No second malignancy * No known chronic liver disease (i.e., active hepatitis, cirrhosis) * No known HIV infection * No significant history of non-compliance to medical regimens or inability to grant reliable informed consent PRIOR CONCURRENT THERAPY: * See Disease Characteristics * No concurrent enzyme-inducing anti-epileptic drugs * No concurrent therapeutic anticoagulation with warfarin (e.g., Coumadin®) * Low-molecular weight heparin (e.g., Lovenox) or heparin allowed * Mini-dose Coumadin® (e.g., 1 mg QD) allowed for prophylaxis of central venous catheter thrombosis, at the discretion of the treating physician * No concurrent acetaminophen (Efferalgan®, Tachipirina®) allowed during imatinib mesylate administration * No other concurrent anticancer agents, including chemotherapy or biological agents * No other concurrent investigational drugs