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