Locally Advanced Thyroglossal Duct Cyst Carcinoma Presenting as a Neck Mass

Abstract

Thyroglossal duct cyst carcinoma is rare and occurs in just 1% of cases with thyroglossal duct cysts. It is not always possible to distinguish a thyroglossal cyst harboring malignancy from its benign counterparts unless biopsied, thus posing the dilemma. Currently there is no clear consensus on the optimal management of thyroglossal duct cyst carcinoma. Here we present the case of a 69-year-old female who presented with a midline neck mass and dysphagia and was found to have papillary thyroid cancer in the biopsy specimen of the neck mass. She underwent excision of the mass and the thyroglossal duct cyst along with total thyroidectomy; however, the thyroidectomy specimen showed no malignancy. Her lymph node mapping was negative and she is awaiting radioactive iodine treatment.

Figure 1

Transverse view of the CT neck that showed presence of a neck mass measuring 28.6 mm × 18.2 mm.

Figure 2

Axial view of the CT neck that showed presence of a neck mass measuring 25 mm in superior to inferior dimension.

Figure 3

Central neck soft tissue demonstrating a cystic structure, within which is a proliferation of fibrovascular cores (H&E stain, 40x original magnification).

Figure 4

The cystic structure is lined by respiratory-type epithelium, consistent with thyroglossal duct cyst (H&E stain, 400x original magnification).

Figure 5

The proliferative tumor is characterized by complex and arborizing papillary fronds (H&E stain, 200x original magnification).

Figure 6

High-power view of the tumor, demonstrating cells with nuclear grooves, peripheralization of chromatin, and some prominence of nucleoli, diagnostic of papillary thyroid carcinoma (H&E stain, 400x original magnification).