In particular, type 2 multiple endocrine neoplasia (MEN2) is an autosomal dominant inherited endocrine malignancy syndrome, due to germline mutations in the REarranged during Transfection (RET) proto-oncogene, which encodes a tyrosine kinase receptor involved in cell growth, differentiation and survival. This evidence concerns the gene NTRK1 and multiple endocrine neoplasia type 2.