TP53 and neuroblastoma: In HR-NB, mutations in the p53 or RAS-MAPK pathways, including ALK, together with telomere maintenance caused by induction of telomerase or ALT (alternative lengthening of telomere) are thought to increase tumor aggressiveness, resulting in even poorer survival among patients with HR-NB.55,56 As MYCN leads to upregulation of TERT expression, MNA associated with any ALK alteration might lead to inferior outcome.