- Arm III: Beginning on day 28 of consolidation chemotherapy, patients receive interim maintenance I chemotherapy comprising VCR IV; escalating doses of MTX IV on days 0, 10, 20, 30, and 40; and MTX IT on day 30. Patients then receive delayed intensification chemotherapy as in arm I. Patients receive interim maintenance II chemotherapy as in interim maintenance I chemotherapy, but with IV MTX starting at 2/3 of the maximum tolerated dose (MTD) attained in interim maintenance I chemotherapy. Patients then receive maintenance chemotherapy as in arm I.