Unresectable localized neuroblastoma: improved survival after primary chemotherapy including carboplatin-etoposide. Neuroblastoma Study Group of the Société Française d'Oncologie Pédiatrique (SFOP).

Neuroblastomas (NBs) were assessed according to INSS recommendations including MIBG scan and extensive bone marrow staging to eliminate metastatic spread. Patients with unresectable tumour received primary chemotherapy including two courses of carboplatin-etoposide (CE) and two of vincristine-cyclophosphamide-doxorubicin (CAdO). Post-operative treatment was to be given only in children over 1 year of age at diagnosis who had residual disease or lymph node (LN) involvement. Between 1990 and 1994, 130 consecutive children were registered. In comparison with resectable primaries, these tumours were more commonly abdominal, larger and associated with N-myc amplification (NMA). Complete, very good and partial response (CR, VGPR, PR) to CE were, respectively, 1%, 7% and 44%, overall response rate (RR) to two courses of CE and two courses of CAdO was 71%, and the tumour could be removed in all but four of the children. The toxicity was manageable. The 5-year overall survival (OS) and event-free survival (EFS) were, respectively, 88% and 78% with a median follow-up of 38 months. In multivariate analysis, only NMA and LN involvement adversely influenced the outcome, particularly NMA. Children with unresectable NBs and no NMA fared as well as children with resectable ones as OS were, respectively, 95% and 99% and EFS 89% and 91%. Our data show encouraging results in localized but unresectable NBs as 90% of children may be considered as definitely cured, especially those without NMA.