Papillary thyroid carcinoma in thyroglossal cyst in a young female

Abstract

ABSTRACT Ectopic thyroid tissue is rare, with a reported incidence of 1 in 300,000. A thyroglossal duct cyst is the most common developmental anomaly of the thyroid gland. The probability of carcinoma arising in such tissue is <1%. The incidence of papillary carcinoma of the thyroid is more in 30–50 years. Here, we report a case of an 18-year-old female presenting with anterior neck swelling, found to have a thyroglossal cyst, fine-needle aspiration cytology (FNAC) of which showed a cystic mass with sparse epithelial cells. After the Sistrunk surgery, biopsy showed classic papillary carcinoma of the thyroid. She underwent total thyroidectomy followed by thyroxine replacement. Thyroglossal cyst papillary carcinoma of the thyroid is a rare entity in young whose diagnosis is easily missed on FNAC; a thorough examination of the biopsy specimen is required. Management should be considered based on multiple associated factors. Overall, the prognosis of it is very good, with a 5-year survival rate of 95%.