LAUSR

Ectopic thyroid tissue (ETT) occurs due to a disorder in the embryonic development of the thyroid gland with incomplete migration of the thyroid tissue from the median plate of the floor of the pharyngeal gut to its usual site. ETT is a rare entity, with an estimated prevalence of 1/100 000–300 000 in the general population, increasing to 1/4000–8000 in patients with thyroid dysfunction. The mechanisms responsible for thyroid morphogenesis have not yet been fully elucidated but certain transcription factors such as TITF1/NKX2-1, PAX8, HHEX or FOXE1 play a key role in this process. ETT mainly affects young women and is often asymptomatic.1 In 90% of the cases, ETT is located at the base of the tongue. …