Sporadic and familial medullary thyroid carcinoma: state of the art.

Medullary thyroid cancer (MTC) accounts for 5% to 10% of all thyroid cancers. The high frequency of familial cases mandates screening and genetic testing. The aggressiveness and age of onset of familial MTC differs depending on the specific genetic mutation, and this should determine the timing and extent of surgery. Sporadic MTC can present at any age, and it is usually associated with a palpable mass and the presence of nodal metastases. Surgery is standard treatment for any patient presenting with resectable MTC. Further studies are needed to investigate the role of radiation therapy in the palliation and local control of postresection and advanced-stage MTC. New systemic therapies for metastatic disease are being investigated. Targeted molecular therapies, based on knowledge of the pathways affected by RET mutations, are being tested in multiple clinical trials.