Current management of medullary thyroid cancer.

Medullary thyroid carcinoma (MTC) is an uncommon malignancy of the parafollicular C cells of the thyroid, with a propensity for early lymph node spread and distant metastasis. It is hereditary in approximately 25% of cases, involving specific point mutations of the RET proto-oncogene inherited in an autosomal dominant fashion. While European professional organizations have put forth calcitonin screening guidelines for earlier detection of MTC, the American Thyroid Association, which has published recent guidelines for MTC treatment, have not had a position on routine screening in the USA. Surgical extirpation of the primary tumor and involved lymph node metastases is the mainstay of treatment and the only chance for cure. Conventional systemic chemotherapies for metastatic MTC have been disappointing; however, newer agents which affect specific RET proteins and tyrosine kinase growth factor receptors show promise in phase 1 and 2 clinical trials.