"Incidental Papillary Thyroid Cancer in Thyroglossal Duct Cyst": A Case Report

Papillary thyroid cancer (PTC) in thyroglossal duct cyst (TGDC) is an infrequent condition with less than two hundred cases described in literature, with an incidence likely to be close to 1%. While its management is quite straightforward, there exists significant controversy regarding whether additional treatment is needed to manage incidentally noticed carcinoma in TGDCs.

A 37-years-old man came to us complaining of a slowly progressive neck mass located in the midline from 4 years ago. Ultrasonography (US) showed a mixed tumor with cyst predominance of 90x79x50 mm and Computed-Tomography (CT) revealed a mixed inframentonian heterogeneous tumor associated with small, mostly peripheral calcifications. The mass was resected using Sistrunk's surgery. Histologic review reported a moderately differentiated papillary carcinoma in thyroglossal duct cyst, without vascular and lymphatic invasion. After two months, a total thyroidectomy was done, to which the pathological report informed normal thyroid.

Thyroglossal duct cyst carcinoma is a rare entity. Management should be decided on single risk stratification. In all cases, a Sistrunk surgery would be accomplished in order to remove the tumor. The reason for thyroidectomy in individuals with a normal thyroid is due to the probability of presenting an intraglandular thyroid cancer concomitantly. It also enables the management with radio-iodine and patient follow up by quantifying thyroglobulin levels.