Papillary carcinoma of the thyroid metastatic to the parapharyngeal space.

The parapharyngeal space is a complex anatomic area which can give rise to a variety of both primary and metastatic neoplasms. Squamous cell carcinoma can also present as a parapharyngeal space mass, either by direct extension or by metastases. Occult thyroid carcinoma presenting as a parapharyngeal space mass is a rare clinical occurrence which has been only sporadically reported in the medical literature. We present a case of occult papillary thyroid cancer with parapharyngeal space metastasis in the form of an isolated tumor, as well as a review of the literature on similar presentations. This rare situation has been previously described only once in the medical literature. Metastatic thyroid cancer should be considered in the differential diagnosis of a parapharyngeal space mass.