Within the subgroup of patients with MYCN non‐amplified neuroblastoma and age ≥ 18 months (N = 47), somewhat smaller differences were observed; a ≥ 90% decrease in persistent neuroblastoma cells was seen in 28% (p = 0.005) of tumors following induction therapy, while no appreciable alterations in necrosis were seen, in keeping with the nature of tumors without MYCN amplification (Table 5). This evidence concerns the gene MYCN and neuroblastoma.