Medullary Thyroid Carcinoma: Recent Advances and Management Update

Abstract

Medullary thyroid carcinoma (MTC) is a malignancy of the thyroid C-cells that comprises 5-10% of all thyroid cancers. MTC occurs in both sporadic and familial forms, the latter making up 25% of all MTCs and being comprised of three distinct syndromes--multiple endocrine neoplasia type 2A (MEN 2A), multiple endocrine neoplasia type 2B (MEN 2B), and familial medullary thyroid carcinoma (FMTC). To date, screening for MTC has been performed using the pentagastrin stimulation test, which is a provocative test for calcitonin release. Germline mutations in the RET protooncogene have been identified in families manifesting these syndromes and genetic screening of individuals at risk of one of these syndromes has become integral to their clinical management. The majority of the mutations associated with MEN 2A and FMTC are tightly clustered in a cysteine-rich region of the RET receptor. A single mutation associated with MEN 2B is in the the tyrosine kinase domain of the RET receptor. Somatic mutations have been identified in the tumor tissue of individuals with sporadic MTC and may prove to be helpful markers in discerning the hereditary or sporadic nature of the MTC. There is general agreement that the primary operation for MTC should include total thyroidectomy and central neck lymph node clearance. The role of microdissection for recurrent disease awaits longitudinal evaluation. External radiotherapy, radionuclide therapy, and chemotherapy may have a role in palliation, but have not been proven to have a curative value. Prognostic factors are discussed.

Elevated level of serum carbohydrate antigen 19.9 as predictor of mortality in patients with advanced medullary thyroid cancer

“…Medullary thyroid carcinoma (MTC) is a neoplasia derived from the parafollicular C-cell of the thyroid and accounts for 1-2% of thyroid malignancies (1,2,3). MTC can occur sporadically (70-80% of the cases) or as part of the MEN2 syndrome (20-30% of the cases) (4,5).…”

Additive effect of RET polymorphisms on sporadic medullary thyroid carcinoma susceptibility and tumor aggressiveness

“…Medullary thyroid carcinoma (MTC), a malignant tumor originating in parafollicular C cells of the thyroid, represents 5-10% of all thyroid cancers (1,2). About 75% of all MTCs are sporadic whereas the remaining patients have an inherited cancer syndrome known as multiple endocrine neoplasia type 2 (MEN2).…”

Molecular genetic diagnostic program of multiple endocrine neoplasia type 2A and familial medullary thyroid carcinoma syndromes in Hungary

“…Medullary thyroid carcinoma (MTC) arises from parafollicular C-cells and may occur in sporadic (75%) or hereditary (25%) form (Marsh et al 1995). Multiple endocrine neoplasia type 2 (MEN2) refers to autosomal dominantly inherited forms of MTC: multiple endocrine neoplasia type 2A, 2B (MEN2A, MEN2B) and familial MTC (FMTC).…”