THE ROLE OF CHEMOTHERAPY IN THE TREATMENT OF CHILDREN WITH NEUROBLASTOMA STAGE-IV - THE GPO (GERMAN-PEDIATRIC-ONCOLOGY-SOCIETY) EXPERIENCE

340 consecutive patients with neuroblastoma stage IV were analyzed for the possible impact of chemotherapy on general condition, remission status, event free survival and survival. The children entered the trials NB 79, NB 82 and NB 85 of the German Pediatric Oncology Society (GPO). The patients did benefit from chemotherapy by considerable improvement of the general condition, by achievement of 30-40% complete and 60-70% partial remissions. The event free survival (EFS) rate 5-8 years after diagnosis was 13% for all 299 protocol patients, the survival (S) rate 10%. The median/mean EFS time were 11.6/23.8 months, the median/mean S time 17.0/29.4 months. The use of response rates as early predictors for long term survival is challenged. Addition of PCVm (cisplatinum, cyclophosphamide, Vm 26) to ACVD (adriamycine, cyclophosphamide, vincristine, dacarbazine) in trial NB 82 resulted in an improvement of the long term EFS rate from 5% to 18% (S rates 7 → 21%). The introduction of IVp (ifosfamide, VP16) and increase of doses (cisplatinum, Vm 26) did not further improve the results. Maintenance therapy (NB 82) revealed a positive influence on the outcome. Shorter intervals for realization of chemotherapy were associated with a trend for better EFS (NB 85). Although the group of children with bone marrow transplantation showed better EFS and S data compared to the unselected chemotherapy group, the advantage was less clear if matched pairs (remission status at the time of BMT) were compared. We conclude from our series that data for further increasing the chemotherapeutic aggressiveness in the treatment of children with stage IV neuroblastoma currently do not exist, but prolongation of the chemotherapy phase might be a worthwhile consideration for future trials.