To evaluate the clinicopathological features and identify the risk factors for distant metastasis in patients with papillary thyroid carcinoma (PTC).

The medical records of sixteen patients who were diagnosed with PTC with distant metastasis from January 2003 to December 2017 were reviewed. Bilateral total thyroidectomy was performed in 16 patients. A retrospective analysis was performed on clinical and pathological features and prognosis.

Of the 16 patients with distant metastasis, thirteen had synchronous metastasis. Two patients died of thyroid carcinoma. Thirteen patients had lung metastases. The median age is 35 years. The average diameter of the tumor was (2.9±1.89) cm. Eleven patients had lateral cervical lymph node metastases. The average number of metastatic lymph nodes reached 9.75. The average maximum diameter of metastatic lymph nodes was (2.5±1.50) cm. Vascularity at power Doppler ultrasonography was found in 10 cases, accounting for 90.9% (10/11). Thyroglobulin (TG) was significantly increased in 8 patients.

Distant metastasis of PTC can be fatal. More attention should be paid for patients with large diameter primary tumor and more enlarged lymph nodes, vascularity at Doppler ultrasonography and elevated TG, the occurrence of distant metastasis, especially lung metastasis.