Thyroglossal Duct Papillary Thyroid Carcinoma and Synchronous Lingual Thyroid Atypia.
OBJECTIVE We report an extremely rare case of the simultaneous occurrence of a thyroglossal duct cyst and a lingual thyroid in the absence of an orthotopic thyroid gland, in a seven-year-old girl from South India. METHOD Case report and a review of the English language literature on the subject. RESULTS The patient presented with a mass on the tongue that had been present for three years, and an anterior neck swelling that had been present for two years. Examination revealed a midline, pinkish, firm mass present on the posterior one-third of the tongue. The neck showed a midline cystic swelling in the infrahyoid position. Radiological imaging confirmed the clinical findings, revealing the absence of her thyroid gland in the normal location. Sistrunk's procedure was performed leaving behind a lingual thyroid. At 13-month follow up, the patient was euthyroid with no recurrence. CONCLUSION To our knowledge the association of a lingual thyroid and a thyroglossal cyst has only been reported once in the literature. The presence of a lingual thyroid in the absence of a normally located thyroid gland or functioning thyroid tissue along the thyroglossal tract, confirmed by radionuclide and computed tomography imaging, may indicate the failure of the normal descent of the thyroid gland during embryonic development. This probable absence of the descent of the thyroid raises questions regarding the origin of thyroglossal duct cysts.