Introduction:
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.
 
Case Report:
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.
 
Conclusion:
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.