SHH and Mobius syndrome: The WHO studies have highlighted four subgroups of MBs: the WNT subgroup (approximately 10% of MBs), and the sonic hedgehog (SHH) subgroup (approximately 30%), associated with a better prognosis, in contrast to subgroups 3 (approximately 25%) frequently associated with metastasis, and 4 (about 35%) the most aggressive MBs, characterized by a high recurrence rate due to a high potential for metastatic dissemination (38).