Thyroglossal duct cyst masquerading as a laryngocele.

Thyroglossal duct cysts (TGDCs) are the most common congenital neck mass and often present in the paediatric population as a painless mass in the midline. A lateralised neck mass presenting for the first time in an adult may raise more concern for malignancy or a laryngocele. A 50-year-old man presented with an asymptomatic right level II neck mass adjacent to the thyroid cartilage. Preoperative CT revealed a cystic mass right of the midline with an intralaryngeal component. Intraoperatively, the lesion tracked towards the central hyoid bone; a Sistrunk procedure was performed. Postoperative pathology revealed a small foci of thyroid tissue within the mass. Careful consideration of the origin of this unusually presenting TGDC enabled appropriate operative management. © BMJ Publishing Group Limited 2019. No commercial re-use. See rights and permissions. Published by BMJ.