Retropharyngeal node metastasis from papillary thyroid carcinoma

Papillary thyroid carcinomas commonly metastasize to paratracheal and jugular lymph nodes. Metastasis to the retropharyngeal node is rare for this tumor.

Five patients underwent surgical treatment for metastasis of thyroid papillary carcinoma to the retropharyngeal lymph nodes that presented as a parapharyngeal or retropharyngeal mass. All patients had a history of total or subtotal thyroidectomy as their initial treatment. Among them, 3 patients had undergone ipsilateral modified radical neck dissection at their initial treatment. The other 2 patients had a history of bilateral or ipsilateral modified neck dissection for their subsequent cervical lymph node metastases.

Metastatic retropharyngeal nodes were successfully resected via transcervical approach in all patients. Although aspiration and difficulty in swallowing were observed in 2 patients after surgical treatment for metastatic retropharyngeal nodes, these complications spontaneously resolved within a few months.

This study suggests that neck dissection and/or metastatic cervical lymph nodes might alter the direction of lymphatic drainage to the retrograde fashion, resulting in the unusual metastasis to the retropharyngeal lymph nodes. Although the cases described here are rare, metastasis to the retropharyngeal node should be considered at the follow-up for thyroid papillary carcinoma. Because these metastases will be missed by routine ultrasonography of the neck, periodic CT scan or MRI is recommended for follow-up, especially for patients with a history of neck dissection.