Thyroglossal Duct Cyst within Midline and Paramidline Location: A Case Report

Introduction: Thyroglossal duct cyst is an embryological congenital malformation of the thyroid gland and accounts for 70% of the congenital neck masses and approximately 7% of the population has thyroglossal tract remnants. Between 7 and 10 weeks of gestation, the thyroglossal epithelial tract obliterates. Failure of the thyroglossal duct tract to obliterate can result in the formation of thyroglossal duct cysts. Objective: We report one case of thyroglossal duct cyst occurring at the concurrent location in the midline and right paramidline of the anterior neck, difference relevant to evidence-based literature in the adult. Resumed Report: A 29-year-old man presented with a painless midline neck swelling, which had been progressively increasing in size for 1 month. The examination revealed an anterior midline neck mass and a cystic nodule at the level of the hyoid bone. Besides, the mass moved with swallowing as well as on tongue protrusion. Ultrasonography of the neck revealed mixed cystic-solid nodules and it did not communicate with the thyroid gland. A computed tomography scan showed a 3.42 cm × 2.69 cm sized hypodense mass at the infrahyoid, midline, and right paramidline of the anterior neck. The patient underwent Sistrunk operation and a histopathological examination identified thyroglossal duct cyst, nonneoplastic cystic and no evident signs of malignancy. Conclusion: Thyroglossal duct cyst located paramidline in adult is a differential diagnosis of anterior midline neck mass. In our patient, there was a rapid growth type, however, the cyst was not infected. Moreover, the resection of the thyroglossal duct cyst by Sistrunk procedure is an adequate surgical approach.