Papillary carcinoma arising in a thyroglossal duct cyst

A 21-year-old lady was admitted with a one year history of painless swelling in the neck. The clinical features and radiological findings suggested a thyroglossal duct cyst. Histology of the excised duct cyst showed papillary carcinoma. Ultrasound examination of the thyroid gland was normal. The patient is on regular follow-up and is well two years following surgery.