MYCN and neuroblastoma: Patients with tumors bearing ALK amplification at relapse were significantly younger than patients with ALK non-amplified tumors in the entire cohort (23.0 versus 42.7 months, P = 0.040, Fig. 3d) and in the subgroup of high-risk patients (23.0 versus 44.6 months, P = 0.009), while it did not differ between ALK-amplified and non-amplified tumors in the subgroup of patients with MYCN-amplified neuroblastoma (23.0 versus 29.0 months, P = 0.156).