A Rare Case of Synchronous Cervical Lymph Node Metastasis from Renal and Thyroid Cancer

Papillary thyroid cancer (PTC) has a propensity to metastasize to the cervical lymph nodes (LNs). Renal cancer (RC) can also spread to the cervical LNs and is the most common cause of metastatic infiltration of the thyroid gland. We describe here the case of a 71-year-old patient with a previous history of surgically treated RC who underwent evaluation of a large left cervical mass. Initial cytological investigation on fine needle aspiration (FNA) indicated metastatic PTC. Computed tomography (CT) scanning revealed no other suspicious foci. The patient underwent total thyroidectomy and central and left lateral cervical LN dissection, during which a large neck mass along the left jugular vein was also removed. Histology demonstrated metastatic spread of RC to the thyroid gland and lateral cervical LNs and concurrent LN metastases from PTC. One LN showed evidence of synchronous RC and PTC metastasis. Only a small papillary thyroid microcarcinoma with no aggressive histological features was detected in the thyroid, raising the possibility that the primary focus of metastatic PTC was the large left lateral neck mass. The patient was discharged after successful treatment for transient hypoparathyroidism. The synchronous presence of RC and PTC in the thyroid and cervical LNs and the concurrent metastases in one of the LNs renders this case unique. Evaluation of a cervical mass in a patient with a prior history of malignancy can prove vexing, and surgery may be the only option for the establishment of a definitive diagnosis.