Adverse outcome of infants with metastatic neuroblastoma, MYCN amplification and/or bone lesions: results of the French Society of Pediatric Oncology

To assess the relevance of MYCN amplification and bone lesions in stage 4 n euroblastoma (NB) in infants aged <1 year, 51 infants with stage 4 NE were enrolled. Three groups of patients were defined according to the type of me tastases and the resectability of the primary tumour. Group I comprised 21 infants with radiologically detectable bone lesions, Group II 22 patients w ith an unresectable primary tumour and Group III eight patients with only m etaiodobenzylguanidine (MIBG) skeletal uptake. MYCN oncogene content was as sayed in 47/51 tumours and found to be amplified in 17 (37%). The 5-year ev ent-free survival (EFS) rate of these 51 infants was 64.1% (+/- 7.1%). In a univariate analysis, bone lesions, MYCN amplification, urinary vanillylman delic/homovanillic acid ratio and serum ferritin levels adversely influence d outcome. In the multivariate analysis, radiologically detectable bone les ions were the most powerful unfavourable prognostic indicator: the EFS rate was 27.2% for these infants compared to 90% for infants without bone lesio ns (P < 0.0001). Our data emphasize the poor prognosis of infants affected by stage 4 NE with bone lesions, especially when associated with MYCN ampli fication. Given the poor results in this group whatever the treatment, new therapeutic approaches need to be investigated in the future. (C) 2000 Canc er Research Campaign.