CONTINUATION II (WEEKS 42-104): Patients receive vincristine sulfate IV on days 1, 29, and 57; dexamethasone IV or PO BID on days 1-5, 29-33, and 57-61; methotrexate IT on day 1; methotrexate PO on days 8, 15, 22, 36, 43, 50, 64, 71, and 78; and mercaptopurine PO on days 8-28, 36-56, and 64-84. Treatment repeats every 12 weeks for 2 years from diagnosis.