Context: Differentiated thyroid cancer (DTC) in thyroglossal duct cysts is uncommon. The requirement of total thyroidectomy and lymph node dissection is still controversial.
Setting: The study was performed in a referral thyroid cancer center at an academic hospital.
Patients: We conducted a single center retrospective study of a consecutive series of 26 patients with DTC in thyroglossal duct cyst, all having undergone cyst resection and total thyroidectomy.
Main outcome measures: Diagnostic modalities, surgical treatment, histopathological features, and clinical outcome were included in the study.
Results: Thyroglossal duct cyst cancer histotype was papillary in 23 of 26 patients (88.5%) and follicular-Hurthle in 3 of 26 cases (11.5%). A concomitant papillary DTC in the thyroid gland was found in 16 of 26 cases (61.5%), and it was multifocal in 8 of 16 cases (50%). At presentation, the patients with cancer in both the thyroglossal duct cyst and the thyroid were older than the patients who only had cancer in the thyroglossal duct cyst (44.9 ± 7.6 vs 32.0 ± 12.7; P = .006). Lymph node dissection, performed in 17 of 26 patients (65.4%), indicated that the central compartment was involved in 6 patients (35.3%, all having cancer also in the thyroid), the laterocervical compartments in 10 patients (58.8%), and the submental in 4 (23.5%). Six patients (23.1%) had persistent disease at 6-year median follow-up.
Conclusions: DTC in thyroglossal duct cysts occurs at a younger age and with more aggressive features at presentation. Concomitant cancer in the thyroid and lymph node metastases is present in most cases. Lymph node compartment involvement is different from that of cancers in the thyroid gland. Therefore, surgical treatment should include both thyroglossal duct cyst resection and total thyroidectomy, with individualized surgical nodal dissection. Subsequent management should follow current DTC guidelines.