Risk factors of suprasternal lymph node metastasis in papillary thyroid carcinoma with clinical lateral cervical lymph node metastasis

Background: Metastatic lymph nodes are occasionally found in suprasternal lymph nodes in patients with papillary thyroid cancer (PTC). However, limited studies have examined these lymph nodes thus far. Therefore, we investigated the frequency and risk factors of suprasternal lymph node metastasis in patients with PTC and lateral cervical lymph node metastasis. Methods: A total of 85 patients with cN1b PTC underwent total thyroidectomy, central neck dissection, and ipsilateral selective neck dissection including suprasternal lymph node dissection. We analyzed the correlation between suprasternal lymph node metastasis and sex, age, tumor characteristics, and cervical lymph node metastasis status. Results: Eleven (12.9%) patients had pathological suprasternal lymph node metastasis. Suprasternal lymph node metastasis was associated with tumors located in the inferior pole of the thyroid gland and level IV lymph node metastasis (P=0.005 and 0.014, respectively). Receiver operating characteristic curve analysis indicated that two or more level IV metastatic lymph nodes had the best predictive value for suprasternal lymph node metastasis (P<0.001). Conclusions: In patients with cN1b PTC, especially those with tumors in the inferior pole of the thyroid gland or level IV lymph node metastasis, greater attention should be paid to the suprasternal lymph nodes and suprasternal lymph node dissection should be routinely included as part of selective neck dissection.