Parapharyngeal Metastasis of Papillary Carcinoma of Thyroid Gland: A Case Report and a Review of the Literature.

Papillary carcinoma is the most frequently encountered differentiated thyroid carcinoma. Usually, metastasis occurs along lymphatic pathways in the central compartment and along the jugular chain. Nevertheless, lymph node metastasis in the parapharyngeal space (PS) is a rare but possible event. In fact, a lymphatic pathway has been identified that connects the upper pole of the thyroid and the PS. We describe the case of a 45-year-old man with a two-month history of a right neck mass. He underwent a complete diagnostic path that highlighted the presence of a parapharyngeal mass associated with the presence of a thyroid nodule suspected to be malignant. The patient underwent surgery (thyroidectomy and removal of the PS mass that was found to be a metastatic node of papillary thyroid carcinoma). The aim of this case is to underline the importance of detecting these kinds of lesions. Nodal metastasis in PS from thyroid cancer is a rare occurrence that is not easily detectable by a clinical examination until the metastasis reaches a considerable dimension. Computed tomography (CT) and magnetic resonance imaging (MRI) permit early identification, but unfortunately, these are not usually employed as a first-level imaging technique in patients with thyroid cancer. The treatment of choice is surgery with a transcervical approach that allows for better control of the disease and of the anatomical structures. Non-surgical treatments are usually reserved for patients with advanced disease, with satisfactory results.