Inclusion Criteria:

• Pathologic evidence of an anaplastic oligodendroglioma. For this study, World Health Organization classification criteria will be used. Central pathology review must take place prior to high-dose therapy but need not occur prior to study entry and induction therapy.
• Pathologic evidence of an anaplastic mixed glioma (i.e. oligoastrocytoma). Again, histopathologic diagnosis will be made using World Health Organization classification criteria. To qualify as a mixed tumor there must be a minimum of 25% oligodendroglial element. Central pathology review must take place prior to high-dose therapy but need not occur in advance of enrollment or induction therapy.
• The diagnostic surgical procedure may have been a complete resection, partial resection, or biopsy.
• Karnofsky performance status > or equal to 60.
• Granulocyte count > or equal to 1.5 X 109/L.
• Platelet count > or equal to 100 X 109/L
• SGOT < than or equal to 2X upper limit of normal.
• Serum creatinine < than or equal to 1.5X upper limit of normal
• Bilirubin < than or equal to 1.5X upper limit of normal
• All patients must sign written informed consent.

Exclusion Criteria:

• Systemic or leptomeningeal metastases (excluding contiguous leptomeninges)
• Prior cranial radiotherapy or systemic chemotherapy
• Other concurrent malignancy (with the exception of cervical carcinoma in situ or basal cell carcinoma of the skin) or serious illness if this would interfere with the prescribed treatment.
• Pregnant or lactating women
• Refusal to use effective contraception