A Case of Metastatic Papillary Thyroid Carcinoma in Neck Lymph Nodes Without Primary Tumor in Thyroid Gland.

Metastatic papillary thyroid carcinoma in the lymph nodes without a primary tumor in the thyroid gland is rarely reported. We report the case of a 63-year-old male who had a left neck level II palpable mass. A left cervical mass had previously undergone 2 central needle biopsies, but only atypical cells had been identified. His prior medical history included surgical treatment for prostate cancer 11 years ago. There was no suspicious primary tumor in the endoscopic examination. After the excisional biopsy, the pathologic finding was metastatic papillary carcinoma from the thyroid, and there were no aberrant findings in the thyroid sonography. The patient underwent a complete thyroidectomy, bilateral central neck dissection (CND), and left level IV dissection, along with postoperative radioactive iodine (RAI) therapy. No thyroid lesion and no more positive lymph nodes were found in the final pathology report. Three months later, a radioiodine nuclear scan was performed, although it revealed no abnormal iodine uptake.