Radiofrequency ablation as a novel treatment for lingual thyroid.

Case Report A 10 year old female with an 8 year history of a base of tongue mass presented after two months of increasing size and symptoms of dysphagia (Figure 1). Diagnosis of lingual thyroid (and only functional thyroid tissue) was confirmed by thyroid scan. Resection was performed by transoral endoscopic RF ablation (Figures 2,3). Intraoperatively, the total blood loss was 20cc and time for the procedure was less than 60 minutes. The patient was extubated immediately and tolerated a regular diet and was discharged home within 24 hours. Postoperative follow-up at 3 months showed complete resolution of symptoms with no change in thyroid function. Introduction The development of the thyroid gland occurs during weeks 3 through 7 of embryologic development when the thyroid analage descends from the foramen cecum to its usual pretracheal location. Failure of this process can result in ectopic deposition of thyroid tissue anywhere along the path of descent1. Lingual thyroid occurs as a result of failure to complete this descent2 . Post-mortem studies have shown that up to 10% of the population have remnants of thyroid tissue in their tongue but only approximately 400 cases of clinically apparent lingual thyroid appear in the literature. In 70% of reported cases, the lingual thyroid is the only functioning thyroid tissue and hypothyroidism occurs in 33%2. Age at time of diagnosis is from 6 to 74 years1. Carcinoma of a lingual thyroid is rare and is no more likely than in a normally situated thyroid. A 2009 review of the literature found only 43 reported cases of lingual thyroid carcinoma3. Traditional surgical approaches for removal of symptomatic lingual thyroid result in significant postoperative morbidity. We describe a new modality for treatment of symptomatic lingual thyroid.