An intra-thyroid thyroglossal duct cyst.

Thyroglossal duct cysts can be found in several different locations, although intra-thyroid presentations are rare. We present the case of an 11-year-old patient with a visible neck mass on the right thyroid lobe. On sonogram, it was consistent with a unilocular cyst measuring 2 centimeters in diameter. The cyst did not take up the radioisotope during a gammagram. Fine needle aspiration cytology suggested a diagnosis of thyroglossal duct cyst. At surgery, we found that there were no lesion-dependent thyroglossal tracts; we therefore performed a simple enucleation of the cyst, sparing the rest of the gland. The pathologic examination confirmed that it was an intra-thyroid thyroglossal duct cyst. After 8 months of follow-up, the patient has remained without complications of any kind or recurrence. Only four prior cases of intra-thyroid thyroglossal cysts have been described in the pediatric population. Half of them presented with a typical thyroglossal tract crossing the hyoid and the other half presented an isolated cyst. It is highly unlikely that a cold, cystic, thyroid mass in a child is a thyroglossal duct cyst. Diagnosis is made on the basis of fine needle aspiration cytology and the lesion is treated surgically. A thyroglossal tract must be methodically sought out during intervention, although they frequently do not exist.