The continuation phase of treatment begins after the intensification phase. It consists of cycles of chemotherapy repeated every three weeks and will last until the patient is in remission for two years. The drugs given are: Vincristine; day 1 : Prednisone or Dexamethasone; days 1-5: 6-MP; days 1-14: Methotrexate; weekly: Intra-thecal Methotrexate/Cytarabine/Hydrocortisone: every 18 weeks.