Thyroid carcinoma presenting as a parapharyngeal mass.

Nodal metastases from occult head and neck primaries presenting as a pharyngeal space mass are unusual. In this report, a patient with dysphagia and a large parapharyngeal mass was found to have metastases papillary thyroid carcinoma. Although it is common for such tumors to metastasize to regional lymph nodes, to our knowledge, this is the only reported case of a thyroid neoplasm masquerading as a primary parapharyngeal space tumor. It indicates upward lymphatic spread of tumor to involve the lateral retropharyngeal nodes. This pattern of spread is in keeping with Rouviere's description of a direct lymphatic pathway from the posterior surface of the superior thyroid lobe to the lateral retropharyngeal nodes. The case presentation is intended to alert the reader of this possibility and to emphasize the inclusion of regional metastatic nodal disease as a possible cause of parapharyngeal space masses.