MYCN and neoplasm: We found MYCN amplifications in 23 tumors (20%), rearrangements affecting the TERT locus in 19 tumors (17%) and ATRX mutations in 12 tumors (10%), comprising 7 focal deletions, 4 missense or nonsense mutations and one tumor affected by a structural rearrangement (NBL54) (Figures 1C and S2).