Inclusion Criteria:

- Histologically confirmed meningioma

- Benign, malignant, or atypical disease

- Neurofibromatosis (NF) type 1 or 2 allowed

- Hemangiopericytoma allowed

- Unequivocal evidence of tumor recurrence or progression by MRI or CT scan (on steroid
dosage that is stable for at least 5 days)

- Evaluable residual disease by MRI or CT scan if previously treated with surgical
resection for recurrent or progressive disease

- Newly diagnosed recurrent disease that requires surgical debulking allowed

- Prior standard external-beam radiotherapy, interstitial brachytherapy, or gamma-knife
radiosurgery allowed provided disease has progressed since completion of therapy

- Patients who have had prior brachytherapy or stereotactic radiosurgery must have
confirmation of true progressive disease rather than radiation necrosis based
upon positron-emission tomography or thallium scanning, magnetic resonance
spectroscopy, or surgical documentation

- Patients with a history of NF may have other stable CNS tumors (e.g., schwannoma,
acoustic neuroma, or ependymoma) provided those lesions have been stable in size for
the past 6 months

- Performance status - Karnofsky 60-100%

- More than 8 weeks

- Absolute neutrophil count at least 2,000/mm^3

- Platelet count at least 120,000/mm^3

- Hemoglobin at least 10 g/dL (transfusions allowed)

- No bleeding disorders

- Bilirubin less than 2 times upper limit of normal (ULN)

- SGOT less than 2 times ULN

- PT, PTT, and INR no greater than 1.5 times ULN

- Creatinine less than 1.5 mg/dL

- Creatinine clearance at least 60 mL/min

- No deep venous or arterial thrombosis within the past 6 weeks

- No pulmonary embolism within the past 6 weeks

- No serious active infection

- No prior intracranial hemorrhage

- No concurrent disease that would obscure toxicity or dangerously alter drug
metabolism

- No other malignancy except nonmelanoma skin cancer or carcinoma in situ of the cervix
unless the patient is in complete remission and off all therapy for that disease for
at least 3 years

- No other significant medical illness that would preclude study participation

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective barrier contraception during and for 3 months
after study participation

- At least 1 week since prior interferon or thalidomide

- No concurrent immunotherapy

- Concurrent epoetin alfa allowed

- At least 4 weeks since prior cytotoxic chemotherapy

- At least 2 weeks since prior vincristine

- At least 6 weeks since prior nitrosoureas

- At least 3 weeks since prior hydroxyurea or procarbazine

- No concurrent chemotherapy

- At least 1 week since prior tamoxifen

- No concurrent hormonal therapy

- At least 4 weeks since prior radiotherapy

- No concurrent radiotherapy

- Recovered from prior surgery

- Recovered from all prior therapy

- At least 1 week since prior noncytotoxic therapy (e.g., isotretinoin) except
radiosensitizers

- At least 2 weeks since prior drugs that affect hepatic metabolism

- At least 4 weeks since prior investigational agents

- No concurrent warfarin (heparin or low-molecular weight heparin allowed)

- No other concurrent investigational agents

- No concurrent acetaminophen of more than 500 mg/day

- No other concurrent anticancer therapy