- Regimen C (open to accrual effective 07/21/2000): Patients receive four 28 day courses of the following chemotherapy: carboplatin IV over 4 hours on days 0 and 1 of each course; vincristine IV on days 0, 7, and 14 of the first three courses only; oral temozolomide daily on days 0-4; and G-CSF SC daily beginning on day 5 and continuing until blood counts recover.