Abstract

Thyroglossal duct cysts develop in the persistent remnants of the thyroglossal tract between the origin of the thyroid at the foramen cecum and the final position of the thyroid gland. Thyroglossal duct cyst can present anywhere from the base of the tongue to the manubrium, but its occurrence within the thyroid gland is very rare. We report here on a 41-year-old woman who presented with a cystic thyroid nodule that was due to an intrathyroid thyroglossal duct cyst. The sonogram, showed a hypoechoic nodule that measured 0.7 x 0.6 cm in the left thyroid lobe. Left lobectomy of the thyroid gland was performed and microscopic examination revealed a cyst lined by non-keratinized squamous epithelium, which was consistent with a thyroglossal duct cyst in the thyroid gland. Intrathyroid thyroglossal duct cyst should be considered in the differential diagnosis of a cystic thyroid nodule. This is the first reported case of a intrathyroid thyroglossal duct cyst in a Korean adult.

• Keywords: Thyroglossal duct cyst;Thyroid nodule;