Inclusion Criteria

DISEASE CHARACTERISTICS:

- Histologically confirmed intracranial anaplastic glioma, including any of the
following subtypes:

- Anaplastic astrocytoma

- Anaplastic oligodendroglioma

- Anaplastic mixed oligoastrocytoma

- Other anaplastic gliomas NOTE: Patients with an original histology of low-grade
glioma are allowed provided a subsequent histological diagnosis of an anaplastic
glioma is made

- Must have evidence of tumor recurrence or progression by MRI or CT scan* NOTE:
*Steroid dose must be stable for at least 5 days before scan

- Prior radiotherapy required

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

- Relapsed disease

- Progression after initial therapy (e.g., radiotherapy with or without
chemotherapy)

- No more than 3 prior therapies (initial therapy and treatment for no more than 2
prior relapses)

- Surgical resection for relapsed disease with no anticancer therapy for up to 12
weeks followed by another surgical resection is considered 1 relapse

- For patients who have had prior therapy for a low-grade glioma, the surgical
diagnosis of high-grade glioma is considered the first relapse

- Must be registered in the North American Brain Tumor Consortium Data Management
Center database

PATIENT CHARACTERISTICS:

Age

- 18 and over

Performance status

- Karnofsky 60-100%

Life expectancy

- More than 8 weeks

Hematopoietic

- WBC at least 3,000/mm^3

- Absolute neutrophil count at least 1,500/mm^3

- Platelet count at least 100,000/mm^3

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

Hepatic

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

- SGOT less than 2 times ULN

Renal

- Creatinine less than 1.5 mg/dL

Other

- Not pregnant or nursing

- Negative pregnancy test

- Fertile patients must use effective contraception

- No other cancer within the past 3 years except nonmelanoma skin cancer or carcinoma
in situ of the cervix

- No active infection

- No concurrent serious medical illness

- No significant medical illness that cannot be adequately controlled with therapy or
that would preclude tolerability of study drug

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

PRIOR CONCURRENT THERAPY:

Biologic therapy

- At least 1 week since prior interferon or thalidomide

- No prior poly ICLC

Chemotherapy

- See Disease Characteristics

- At least 2 weeks since prior vincristine

- At least 3 weeks since prior procarbazine

- At least 6 weeks since prior nitrosoureas

- No concurrent chemotherapy

Endocrine therapy

- See Disease Characteristics

- At least 1 week since prior tamoxifen

Radiotherapy

- See Disease Characteristics

- At least 4 weeks since prior radiotherapy

Surgery

- See Disease Characteristics

Other

- Recovered from all prior therapy

- At least 1 week since other prior noncytotoxic agents (e.g., isotretinoin), excluding
radiosensitizers

- At least 4 weeks since prior cytotoxic therapy

- At least 4 weeks since prior investigational agents