RATIONALE: Drugs used in chemotherapy use different ways to stop tumor cells from dividing so they stop growing or die. Thalidomide may stop the growth of cancer by stopping blood flow to the tumor.

PURPOSE: Phase II trial to study the effectiveness of combining temozolomide and thalidomide in treating patients who have recurrent or progressive brain tumor.

OBJECTIVES: I. Determine the efficacy of temozolomide and thalidomide in patients with recurrent or progressive supratentorial glioblastoma multiforme or gliosarcoma. II. Determine the toxicity of this regimen in these patients.

OUTLINE: This is a multicenter study. Patients receive oral temozolomide once daily on days 1-5 and oral thalidomide daily on days 1-28. Treatment repeats every 28 days for a maximum of 24 courses in the absence of disease progression or unacceptable toxicity. Patients are followed at 1 month and then for survival.

PROJECTED ACCRUAL: A total of 40 patients will be accrued for this study within 4-5 months.

DISEASE CHARACTERISTICS: Histologically confirmed supratentorial glioblastoma multiforme or gliosarcoma Must have evidence of tumor recurrence or progression by MRI scan after failing prior radiotherapy Bidimensionally measurable enhancing residual disease on MRI or CT scan Prior recent resection of recurrent or progressive tumor allowed if all of the following conditions apply: Recovered from surgery Residual evaluable disease present that is not artifactual postsurgical enhancement Baseline MRI or CT scan is performed within 14 days prior to study and while on a steroid dose that has been stable for at least 5-7 days

PATIENT CHARACTERISTICS: Age: 18 and over Performance status: Karnofsky 60-100% Life expectancy: At least 8 weeks Hematopoietic: Absolute neutrophil count at least 1,500/mm3 Platelet count at least 100,000/mm3 Hepatic: SGPT less than 2 times normal Alkaline phosphatase less than 2 times normal Bilirubin less than 1.5 mg/dL Renal: BUN or creatinine less than 1.5 times normal Other: Not pregnant or nursing Negative pregnancy test Fertile patients must use one highly effective method of contraception, AND one additional effective method of contraception for at least 4 weeks before, during, and for 8 weeks after study No peripheral neuropathy greater than grade 1 No active infection No other illness that would obscure toxicity or alter drug metabolism No other concurrent serious medical illness No other prior cancer within the past 3 years except nonmelanoma skin cancer or carcinoma in situ of the cervix

PRIOR CONCURRENT THERAPY: Biologic therapy: No prior thalidomide No other concurrent biologic therapy for cancer Chemotherapy: No more than 1 prior chemotherapy regimen At least 3 weeks since prior chemotherapy (2 weeks for vincristine and 6 weeks for nitrosoureas) No other concurrent chemotherapy for cancer Endocrine therapy: See Disease Characteristics No concurrent endocrine therapy for cancer Radiotherapy: See Disease Characteristics No concurrent radiotherapy for cancer Surgery: See Disease Characteristics No concurrent surgery for cancer Other: Recovered from prior therapy No other concurrent investigational drugs for cancer