Fast Five Quiz: Medullary Thyroid Cancer and RET Mutation

Lori J. Wirth, MD


September 08, 2022

Medullary thyroid carcinoma (MTC) arises from the parafollicular C cells of the thyroid and accounts for 3%-5% of thyroid cancers. MTC is more aggressive than most other thyroid cancer subtypes and thus accounts for a higher percentage of thyroid cancer deaths. Sporadic MTC accounts for about 75% of cases; the remaining 25% arise in inherited multiple endocrine neoplasia type 2 (MEN2) A and B, autosomal-dominant syndromes caused by germline-activating mutations in the RET proto-oncogene. A majority of sporadic MTCs also harbor activating RET mutations, though these are somatic rather than germline mutations. Germline RET testing is necessary for all new cases to identify patients with MEN2 A and B. In addition, next-generation sequencing is playing an increasingly important role in MTCs, allowing for identification of tumors harboring activating somatic RET mutations.

How familiar are you with RET mutations in MTC? Test your knowledge with this quick quiz.


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.