The identification of medulloblastoma groups allowed to define three risk groups of patients: low-risk (corresponding to MBWNT) with a 100% OS at five years, high-risk (corresponding to MBgroup3 with MYC/MYCN amplification) with a 20% OS at five years, and intermediate-risk (all the rest of medulloblastomas) with an OS of 65% at five years [184]. This evidence concerns the gene MYCN and medulloblastoma.