Coexistence of a carotid body tumor and thyroglossal duct carcinoma with cervical lymph node metastasis.

Thyroglossal duct carcinoma is uncommon, occurring in approximately 1% of all thyroglossal duct remnants. This rare neoplasm is characterized by relatively nonaggressive behavior with infrequent lymph nodal spread. Another rare neoplasm of the head and neck region is a carotid body tumor. A 78-year-old woman with a 3-year history of midline and bilateral neck masses was referred to us. Fine needle aspiration biopsies and a computed tomography scan suggested the diagnosis of thyroglossal duct carcinoma with cervical lymph node metastasis. Interestingly, the left-side neck mass was found to be splaying the carotid bifurcation, on computed tomography imaging. Carotid arteriography demonstrated a highly vascular mass in the bifurcation of the carotid artery that was compressing the internal and external carotid arteries. To our knowledge, this is the first reported instance of a thyroglossal duct carcinoma with neck metastasis accompanied by a carotid body tumor. In addition, the carotid body tumor in this case mimicked neck metastasis from the thyroglossal duct carcinoma.