SMO and primitive neuroectodermal tumor: Other oncogenic mutations of SMO that are associated with constitutive HH pathway activation include: L412F, which has been reported in desmoplastic MB [88], meningiomas [82], and ameloblastomas, where it has been associated with insensitivity to vismodegib [81]; S533N in primitive neuroectodermal tumors (PNET) [83]; and S278I in both BCC and MB [78,79].