Medullary thyroid carcinoma (MTC) is a rare tumor representing 5–10% of thyroid cancers, with a 10-year survival rate is about 50–75%. It arises from a particular thyroid cell type: the parafollicular C-cells of the thyroid which secrete calcitonin (CT). Serum CT is a very sensitive and specific method for diagnosing MTC, however, the potential role of calcitonin receptor (CTR) expression on tumor aggressiveness and prognosis remained to be explored.
