SIMULTANEOUS METASTASES OF PAPILLARY THYROID CARCINOMA AND NEUROENDOCRINE TUMOR OF THE CECUM TO CERVICAL LYMPH NODES: A CASE REPORT.

We present a case of a patient with simultaneous cervical lymph node metastasis of papillary thyroid cancer (PTC) and cecum neuroendocrine tumor (NET). A 45-year-old male patient with the diagnosis of metastatic NET of the cecum underwent fine needle aspiration (FNA) of a positron emission tomography with 18F-fluorodeoxyglucose (18F-FDG PET) positive nodule in the left thyroid lobe. Due to FNA finding suspect of PTC, the patient underwent total thyroidectomy with central neck dissection. Histopathologic finding revealed PTC of the left thyroid lobe and small solitary lymph node PTC metastasis in the central neck region. Postoperative evaluation with neck ultrasound (US) revealed two enlarged suspected lymph nodes in cervical regions III and IV on the left side of the neck and the patient underwent FNA with measurement of thyroglobulin (Tg) in the aspirates. The FNA finding of the cervical lymph node in the region III revealed PTC metastasis with high Tg value in the aspirate, while FNA finding of the cervical lymph node in the region IV revealed NET metastasis with low Tg value in the aspirate. Postoperative serum Tg value was 17.75 µg/L and the patient underwent 5550 MBq iodine-131 (I-131) therapy. A year after I-131 therapy, follow-up neck US demonstrated complete cure of PTC cervical lymph node metastasis in the region III and stable in size NET cervical lymph node metastasis in the region IV. To our knowledge, this is the first report of simultaneous occurrence of cervical lymph node metastases of PTC and NET of the cecum.