Combined chemotherapeutic regimens of (1) cyclophosphamide (40 mg/kg x two days), (2) cisplatinum (20 mg/m2 x five days) plus VM-26 (100 mg/m2), and (3) Adriamycin (60 mg/m2) plus DTIC (250 mg/m2 x five days) were prescribed for 42 Japanese children greater than 1 year of age with stage III or IV neuroblastoma. The protocol was separated into three forms (A, B, and C) from the combination pattern of three such high-dose courses. The cumulative survival rates for those with stages III and IV 48 months after initiation of therapy were 76.2% and 20.1%, respectively, and the overall rate was 36.7%. The tumor disappeared during the course of treatment in 25 of 42 children (59.5%). The 48-month survival rate was superior in patients greater than 5 years of age than younger patients (P less than .01). Even in patients with a tumor originating in the suprarenal region, the 48-month survival rate was 30.5%. Among 12 patients in whom the N-myc oncogene was measured, one of five with one to ten copies of amplification died, whereas all seven with greater than ten copies died or had a recurrence. Thus, the present chemotherapeutic regimens, in particular alternate administration of each high-dose course, considerably improved the survival of patients with stage III neuroblastoma. More aggressive protocols are needed for those with stage IV neuroblastoma who are greater than 1 year of age, particularly in those with an amplified N-myc oncogene.