Thyroglossal duct cyst with papillary carcinoma: what must be done?

OBJECTIVE To present a report series of five cases, compare their clinical evolution, and establish the appropriate treatment. METHODS A retrospective study was performed with the clinical records from three health institutions in Mexico City, Mexico, in order to search for patients with histologic diagnosis of thyroglossal duct carcinoma and were classified by different risk stratifications to compare their outcome. RESULTS We found five patients, three females and two males, mean age 49 years. Four were treated by Sistrunk's procedure, total thyroidectomy, radioiodine ablation, and thyroxine suppression; one patient underwent Sistrunk's procedure only. Four patients were classified in the low- and median-risk group and had good outcome; one patient was in the high-risk group and had poor outcome. CONCLUSIONS The thyroglossal duct cyst must be studied in the adult population through fine-needle aspiration biopsy (FNAB) and a frozen section in cases in which FNAB is inconclusive or unavailable. When a diagnosis of a thyroglossal cyst carcinoma is made, an evaluation of the thyroid gland during surgery must be done as well as a careful examination to identify suspicious lymph nodes and neck dissection should be reserved for confirmed adenopathies. When an thyroglossal duct cyst has been excised using Sistrunk's procedure and the definitive histologic analysis reports malignancy, the thyroid gland must be studied. The extension of the surgery must be handled according to the criteria established for differentiated thyroid cancer.