MYCN and neuroblastoma: Multivariate Cox survival analyses including gender (female vs male), age status (<18 months vs ≥18 months), INSS stage (INSS 2/3/4s vs INSS 4), MYCN amplification (non‐amplified vs amplified), COG risk status (low risk vs high risk), ploidy status (hyperploid vs diploid), histology type (favourable vs unfavourable), differentiation (differentiating vs poorly differentiated), MKI (low vs high) and pathology subtype (ganglioneuroblastoma vs neuroblastoma) as covariates were performed.