Patients will receive induction therapy with antimetabolite agents (methotrexate, leucovorin and 5-fluorouracil) for two to four cycles. Patients will then receive consolidation therapy with two cycles of high-dose alkylating agents. First, patients will receive one cycle of high-dose cyclophosphamide administered with growth factor support. PBPCs will be harvested during the recovery phase of the cyclophosphamide cycle.