DISEASE CHARACTERISTICS:

• Histologically confirmed supratentorial glioblastoma multiforme or gliosarcoma
• Completed standard external beam radiotherapy within the past 5 weeks
• Stable disease by MRI or CT scan

PATIENT CHARACTERISTICS:

Age

• 18 and over

Performance status

• Karnofsky 60-100%

Life expectancy

• More than 4 months

Hematopoietic

• Absolute neutrophil count at least 1,500/mm3
• Platelet count at least 100,000/mm3
• No history of bleeding disorder

Hepatic

• Bilirubin less than 1.5 mg/dL
• SGPT less than 2.5 times normal
• Alkaline phosphatase less than 2.5 times normal

Renal

• BUN less than 1.5 times upper limit of normal (ULN) OR
• Creatinine less than 1.5 times ULN

Cardiovascular

• No deep vein thrombosis within the past 3 weeks (must be clinically stable)

Pulmonary

• No pulmonary embolism within the past 3 weeks (must be clinically stable)

Other

• Must participate in System for Thalidomide Education and Prescribing Safety program
• No peripheral neuropathy grade 2 or greater
• No active infection
• No concurrent illness that may obscure toxicity or dangerously alter drug metabolism
• No other serious concurrent illness
• No other malignancy within the past 3 years except nonmelanoma skin cancer or carcinoma in situ of the cervix
• Not pregnant or nursing
• Negative pregnancy test
• Fertile patients must use 2 forms of effective contraception for 1 month before, during, and for 1 month after study

PRIOR CONCURRENT THERAPY:

Biologic therapy

• No prior thalidomide
• No concurrent immunotherapy
• No concurrent prophylactic filgrastim (G-CSF)

Chemotherapy

• No prior chemotherapy
• No other concurrent chemotherapy

Endocrine therapy

• No concurrent hormonal therapy
• Concurrent corticosteroids must be at stable or decreasing dose over the past 7 days

Radiotherapy

• See Disease Characteristics
• No concurrent radiotherapy

Surgery

• No concurrent surgery

Other

• No other concurrent anticancer therapy
• No other concurrent investigational agents