rubia F. FuZZA***

Thyroglossal duct cysts (TDCs) are cervical cysts occurring in approximately 7 % of the population, mainly during childhood. The cyst usually presents itself as a painless, asymptomatic midline swelling below the hyoid bone. Differential diagnosis involves branchial cleft cyst, lymphoepithelial cyst, thyroid gland lesions, ranula and lymphadenopathy (of various etiologies). Sonogram (ultrasound) is the most frequent and appropriate imaging modality in suspected TDC. Preoperative fine-needle aspiration is an inexpensive and safe method that can be considered in selected adult patients, having prime importance to the exclusion of carcinoma. This article presents a TDC of the neck in a 5-year-old boy. Keywords: Thyroglossal cyst; cystic duct; head and neck neoplasms. Concept, epidemiology and pathogenesis Thyroglossal duct cysts (TDC) are usually considered to be a benign embryonic malformation where the thyroglossal duct fails to obliterate after descent of the thyroid gland [3]. The thyroid gland is originally located in the f loor of the pharynx, between the tuberculum impar (the first pharyngeal arch) and the copula (the second and third pharyngeal arches), during the 4th week of fetal life [11]. During development, the thyroid gland reaches its final position in front of the trachea and leaves the thyroglossal duct, a narrow canal with an epithelial lining along the descending route of the thyroid gland. Normally, the thyroglossal duct completely disappears before the 10th week [11, 13]. However, if the thyroglossal duct is not obliterated, the secretory epithelium of the thyroglossal duct may result in a TDC