Prognostic factors in metastatic neuroblastoma in patients over 1 year of age treated with high-dose chemotherapy and stem cell transplantation: a multivariate analysis in 218 patients treated in a single institution

The purpose of this paper is to study prognostic factors in neuroblastoma p atients treated with high-dose chemotherapy and hematopoietic stem cell tra nsplantation, Two hundred and eighteen children over 1 year of age and trea ted for stage 4 neuroblastoma were enrolled in this study. The median age a t diagnosis was 39 months, the sex ratio 1.5 and 84% of patients had an abd ominal primary tumor. Skeletal disease was detected in 79% of cases and bon e marrow involvement in 93%, N-myc oncogene amplification was present in 27 % of the patients studied. The probability of event-free survival at 5 year s post-diagnosis was 29% in this series. Three major favorable prognostic f actors were significant and independent in the multivariate analysis: age u nder 2 years at diagnosis (P < 0.01), absence of bone marrow metastases at diagnosis (P < 0.04) and the high-dose conditioning regimen containing busu lfan-melphalan combination (P = 0.001). The quality of response to conventi onal primary chemotherapy was close to significance (P = 0.053). We conclud e that factors related to the patient (age) and extent of disease are predi ctive of outcome in patients with neuroblastoma treated,vith conventional c hemotherapy followed by surgical excision of the primary and consolidation with high-dose chemotherapy, They should be taken into account in future pr ospective studies. Moreover, the type of conditioning regimen appears to be the most important prognostic factor. This should encourage new investigat ions into innovative drug combinations.