Medullary Thyroid Carcinoma is a rare thyroid tumororiginating from neural crest cells, the C-cell that impliesseveral special features, secretion of differentneuroendocrine markers, association with other endocrinetumors and familial appearance. The familial variant ofmedullary thyroid carcinoma allows an early detection bybiochemical and genetic testing. At that stage acceptablesurgical treatment will cure the patient. The sporadic formof medullary thyroid carcinoma will be diagnosed in aprogressive stage, but adequate surgical procedure can curethese patients too. Long term survival depends on stage,age, sex, and variant of the disease and seems to be as goodas in other differentiated thyroid cancers.