Forty-seven children or adolescents with initial stage IV (42 patients) or stage III (five) advanced neuroblastoma (12 were progressing after relapse and 35 had never reached complete remission [CR] after conventional therapy) were included in a phase II study of the combination of high-dose VP-16 (100 mg/m2/d X 5) and high-dose cisplatin (CDDP) (40 mg/m2/d X 5). Twenty patients had received prior CDDP therapy (total dose, 100 to 640 mg/m2; median, 320 mg/m2) and 38 of 47 had bone marrow involvement when included in the study. The overall response rate was 55%, with 22% CR. Duration of response was 5 to 18 months, with a median of 10 months. Eight patients are still disease free, with a median observation time of 13 months, but all had received additional therapy after two courses of this regimen. Gastrointestinal toxicity was frequent but tolerable. Myelosuppression was severe but of brief duration, ie, nadir of neutrophils was observed at day 15 with 95% of the patients recovering a normal count before day 28, and nadir of platelet count was at day 17 with only two severe and reversible episodes of bleeding. The overall incidence of sepsis was 8% (seven of 92 courses), with no death related to infection. No acute renal failure was observed after two courses, and only three of 47 children experienced a clear reduction of renal function. After two courses, only two children showed a hearing loss in the 1,000 to 2,000 Hz range, although hearing loss above the 2,000 Hz level was frequently encountered. It is concluded that high-dose VP-16 and CDDP is an effective regimen in advanced neuroblastoma with acceptable toxicity. Phase III studies are needed in previously untreated patients. J Clin Oncol 5:941-950.