MTC can be sporadic (somatic mutation, 75% of cases) and hereditary (germline mutation, 25% of cases), with the later form being part of MEN2 syndrome types A and B. MEN2A is the most frequent subtype (95%) and consists of MTC (present 100% of the case), pheochromocytoma (PHEO, up to 50%), primary hyperparathyroidism (PHPT, up to 30%), and with less frequency cutaneous lichen amyloid and Hirschsprung’s disease [1, 2]. This evidence concerns the gene RET and medullary thyroid gland carcinoma.