RATIONALE: Drugs used in chemotherapy use different ways to stop tumor cells from dividing so they stop growing or die.

PURPOSE: Phase I trial to study the effectiveness of irinotecan plus carmustine in treating patients who have recurrent primary malignant glioma.

OBJECTIVES: I. Determine the maximum tolerated dose of irinotecan administered in combination with a fixed dose of carmustine in patients with recurrent primary malignant glioma. II. Determine the toxic effects of irinotecan and carmustine in these patients.

OUTLINE: This is a dose escalation study of irinotecan. Patients receive irinotecan IV over 90 minutes weekly on weeks 1-4 and carmustine IV over 1 hour on weeks 1-6. Treatment continues in the absence of disease progression or unacceptable toxicity. Cohorts of 3-6 patients receive escalating doses of irinotecan until the maximum tolerated dose (MTD) is determined. The MTD is defined as the dose at which no more than 1 of 6 patients experiences dose limiting toxicities.

PROJECTED ACCRUAL: Approximately 18-36 patients will be accrued for this study.

DISEASE CHARACTERISTICS: Histologically proven recurrent primary malignant glioma Measurable recurrent or residual primary central nervous system neoplasm confirmed by MRI

PATIENT CHARACTERISTICS: Age: 18 and over Performance Status: Karnofsky 60-100% Hematopoietic: Hematocrit greater than 29% Absolute neutrophil count greater than 1,500/mm3 Platelet count greater than 125,000/mm3 Hepatic: SGOT less than 1.5 times upper limit of normal (ULN) Bilirubin less than 1.5 times ULN Renal: Creatinine less than 1.5 mg/dL BUN less than 25 mg/dL Pulmonary: DLCO at least 60% Other: Not pregnant Fertile patients must use effective contraception

PRIOR CONCURRENT THERAPY: Biologic therapy: Not specified Chemotherapy: At least 6 weeks since prior chemotherapy No prior irinotecan or carmustine treatment failure No more than 1 prior chemotherapy regimen Endocrine therapy: Patients taking corticosteroids must be on a stable dose for at least 1 week prior to study and the dose should not escalate over entry dose level Radiotherapy: At least 6 weeks since prior radiotherapy Surgery: At least 3 weeks since prior surgical resection Other: No concurrent medication that may interfere with study results