Ectopic Thyroid Tissue in the Thyroglossal Cyst Duct: Rare Clinical Entity with Review of Literature

The ectopic thyroid tissue is a rare developmental abnormality during embryogenesis where the thyroid gland passes from floor of the primitive foregut to its final pretracheal position. Its very important to verify the presence of a normally located normally functioning thyroid gland, thus excluding the possibility of an ectopic thyroid gland which resembles a TDC. A 12-year-old female presented to us with swelling in the midline of the neck region since 1 year. The mass moved with swallowing and protrusion of the tongue. On aspiration biopsy, a colloid material with cyst was confirmed. Imaging showed no orthotopic thyroid tissue on sonography and scintigraphy. No surgical intervention was done and as the patient was hypothyroid, levothyroxine replacement was given and the patient was advised for followup regularly. Hormonal estimation to rule out hypothyroid status and thyroid scintigraphy to detect the ectopic tissue and to see the presence of the normal orthotopic thyroid are essential investigations in evaluating thyroglossal cyst. Surgery is the treatment of choice in symptomatic lingual thyroids, with a role for radioiodine ablation in recurrent disease. Head and neck surgeons should evaluate ectopic thyroid as a differential diagnosis while evaluating mass in the midline as well as lateral neck.