Vol. 101  No. June  2008

Clinical Analysis of 4 Cases of Thyroglossal 
Duct Cyst Papillary Carcinoma

Katsuro Sato and Sugata Takahashi
(Niigata University Faculty of Medicine)

Four cases of thyroglossal duct cyst (TDC) papillary carcinoma treated in our department were clinically analyzed. Patients were 36, 59, 60, and 63 years old, respectively. Although TDC carcinoma was located in the midline of neck in 2 of the 4 cases, the lesion was located atypically in the lateral neck in the other 2 cases. Preoperative diagnoses were TDC carcinoma accompanied by thyroid carcinoma, TDC accompanied by benign thyroid tumor, thyroid carcinoma with cervical lymph node metastasis, and primary unknown metastatic neck carcinoma, respectively. Radiological features included a solid part in the cyst wall on CT in 3 of the 4 cases, and calcification of the solid part in 2 of the 3 cases. In the preoperatively diagnosed as malignant, one case was diagnosed as having malignancy at 5th fine needle aspiration cytology (FNA) during follow-up. The case who was not thought to be malignant preoperatively was diagnosed as papillary carcinoma on intraoperative frozen section (FS) histopathological diagnosis. Three of the 4 cases were accompanied by thyroid gland papillary carcinoma and total thyroidectomy was performed. In the diagnosis of patients with cervical cystic mass, TDC carcinoma should be considered even when the lesion arises in elderly patients or in the lateral neck. On radiological diagnosis, the presence of a solid portion as well as calcification were important CT finding. Repeated FNA and FS histopathological diagnoses were essential for the accurate diagnosis and treatment of TDC carcinoma. In the patient with TDC carcinoma arising in the midline accompanied by thyroid carcinoma, dissection by Sistrunk's procedure, total thyroidectomy and paratracheal dissection followed by isotope therapy is considered a proper treatment strategy. For the lateral neck cases, neck dissection should be done, and total thyroidectomy followed by isotope therapy is needed for patients complicated by thyroid carcinoma.

Key words :
thyroglossal duct cyst, papillary carcinoma, thyroid carcinoma, surgery

第101巻6号 目次   Vol.101 No.6 contents