Analysis of risk factors for posterior laryngeal recurrent nerve metastasis in micropapillary thyroid carcinoma.

Posterior recurrent laryngeal nerve (RLN) lymph node dissection remains controversial in the operation of thyroid cancer, especially in cases of papillary thyroid microcarcinoma (PTMC). The present study aimed to evaluate the risk factors for posterior RLN lymph node metastasis in patients with PTMC. Two hundred and thirty-nine patients pathologically diagnosed with PTMC after surgery between June 2016 and June 2017 were included. Risk factors including age, sex, tumor diameter, multiple tumor focus, membrane invasion and lateral cervical lymph node metastasis condition, were analyzed, and their corresponding OR values were calculated. The results indicated that posterior RLN lymph node metastasis was pathologically identified in 27/239 patients. Membrane invasion (p = 0.024), VIa lymph node metastasis (p < 0.01), and lateral cervical lymph node metastasis (p < 0.01) were considered to be risk factors for posterior RLN lymph node metastasis. It is concluded that membrane invasion, VIa lymph node metastasis, and lateral cervical lymph node metastasis significantly increased the incidence of posterior RLN lymph node metastasis. Complete dissection of the posterior RLN lymph node was essential for patients with these risk factors.