Thyroid tissue as a submandibular mass: a case report

Ectopic Thyroid Presenting as a Submandibular Mass

“…Ectopic thyroid tissue usually occurs in the midline, from the foramen caecum to the mediastinum [1,5,7,9] as a result of abnormal median migration and is rarely present lateral [1,10]. A lingual location is most common, accounting for 90% of the reported cases [1,3,5,6,[8][9][10].…”

“…A lingual location is most common, accounting for 90% of the reported cases [1,3,5,6,[8][9][10]. Other sites rarely involved are the mediastinum, lungs, porta-hepatis system, duodenum, esophagus, heart, breasts, and intra-tracheal area [1][2][3][4][5][6][7][8]. Presence of ectopic thyroid tissue in the submandibular region is extremely rare [1,3,4,[7][8][9][10].…”

“…Other sites rarely involved are the mediastinum, lungs, porta-hepatis system, duodenum, esophagus, heart, breasts, and intra-tracheal area [1][2][3][4][5][6][7][8]. Presence of ectopic thyroid tissue in the submandibular region is extremely rare [1,3,4,[7][8][9][10]. According to a recent study [8], similar cases of ectopic thyroid tissue have been reported in submandibular space.…”

“…The median portion produces the largest part of the thyroid parenchyma while the lateral portions are derived from the fourth pharyngeal pouch accounting for 1-30% of the total thyroid weight [1,5]. A number of anomalies can develop during thyroid formation [2,5], including ectopia of the thyroid tissue, a rare entity [3,[5][6][7], which may or may not coexist with a normal thyroid gland [3,5,6].…”

“…In some rare cases, the lack of merging of the lateral cell clusters with the median can cause a lateral ectopic thyroid gland [1,3]; when this occurs thyroid tissue is located in the submandibular region [1,3,4,[7][8][9][10].…”