SHH and medulloblastoma: The commonest tumor of this group is medulloblastoma, which in the current WHO classification, contain molecularly defined subgroups (WNT-activated, SHH-activated and non-WNT/non-SHH) and histologically defined subgroups (classic, nodular desmoplastic, with extensive nodularity and large cell anaplastic, not otherwise specified—with myogenic differentiation and with melanotic differentiation).