Papillary thyroid carcinoma arising in the wall of a thyroglossal duct cyst.

The thyroglossal duct cyst is the most common anomaly in thyroid development. However, carcinomas arising in a thyroglossal duct cyst are rare entities. To date, approximately 125 cases have been reported, the majority being papillary thyroid carcinomas. In most cases the diagnosis is established only after excision of a clinically benign thyroglossal duct cyst. The etiology of such tumors remains unclear but de novo origin is generally proposed. Controversies exist in relation to a rational and effective therapeutic approach. A further case of thyroglossal duct papillary carcinoma affecting a 55 year-old Spanish man is presented to highlight the clinicopathological features of this condition. Preoperative computed tomography performed on our patient showed irregular calcium deposits adjacent to the hyoid bone. Cytohistological and immunohistochemical studies showed a papillary thyroid carcinoma with abundant psammoma bodies. Surgery consisted only of a Sistrunk procedure. In view of the prolonged course of papillary carcinoma, long-term follow-up is mandatory.