Malignant thyroglossal duct cyst with synchronous occult thyroid gland papillary carcinoma
A 52-year-old male presented to our department with a painless swelling in front of neck progressing slowly over the past 6 years. He complained of a rapid increase in size over the past 6 months. No history of irradiation. Clinical examination and CT evaluation suggested the presence of an irregularly-shaped complex TGDC measuring 6 × 5 cm with solid and cystic components. There was also evidence of fine calcification within the solid areas []. There was also a mildly enhancing nodule found in right lobe and isthmus of thyroid with fine calcification within the nodules. There was no cervical lymphadenopathy. Ultrasound-guided FNAC from the solid area of the TGDC suggested papillary carcinoma. Sistrunk operation for thyroglossal cyst done using a single transverse neck incision, and per-operative thyroid exploration revealed a hard nodule in the right lobe of thyroid with few enlarged paratracheal nodes. Since there was a strong suspicion of malignant thyroid nodule as well, total thyroidectomy and central compartment dissection was completed in the same sitting. Gross examination revealed TGDC, which was multiloculated and had solid and cystic areas (about 2 cm) []. There was a 0.5 cm nodule in the isthmus and a 1 cm nodule in the right lobe of thyroid gland. Microscopic diagnosis [Figures -] was multifocal papillary carcinoma of thyroid and thyroglossal cyst with no metastasis in level VI nodes. Post op I131 scan showed 0.3% uptake in the thyroid bed and no evidence of functioning distant metastasis. Patient is on suppressive thyroxin therapy.