Papillary thyroid carcinoma arising from a thyroglossal duct cyst

Thyroglossal duct cysts (TGDCs) are the most common form of congenital cysts on the neck. The incidence of papillary thyroid carcinoma in TGDC is less than 1%. In most cases, the diagnosis is made postoperatively. We present a case of 22-year-old female with papillary thyroid carcinoma arising from a TGDC, identified in pathologic study after Sistrunk operation. There was no clinical evidence of malignancy in the cyst. There was neither invasion to adjacent tissue nor lymph node involvement. The patient then underwent total thyroidectomy and bilateral neck dissection. The patient was treated with radioactive iodine and thyroid suppression therapy was given as adjuvant treatment. She has been followed-up for 2 years without any metastasis. Because of the rarity of TGDC, this diagnosis may be missed, drastically affecting the appropriateness of the treatment provided. Surgeons should be aware of TGDC in surgical planning and postoperative treatment and should include this pathology in differential diagnosis of anterior midline neck masses