In summary, the histopathological and molecular findings—consistent with a small round blue cell tumor in the cerebellum, high proliferative activity, expression of neuronal markers (NF+MAP2+SYN+), and a characteristic methylation profile—support the diagnosis of medulloblastoma, SHH-activated, TP53-wildtype, CNS WHO grade 4. This evidence concerns the gene SHH and medulloblastoma.