Factors Related To Contralateral Central Lymph Node Metastasis In Clinically Node-negative Papillary Thyroid Carcinoma

Objective: This study analyzed the factors related to metastasis of contralateral central lymph node(CLN)in c N0 papillary thyroid carcinoma and discusses the indications for CLN dissection.Methods: We enrolled 149 unilateral PTC patients who underwent total thyroidectomy and prophylactic bilateral central lymph node dissection.This work analyzed the relationship of gender,age,extrathyroidal extension,multifocality,thyroiditis,ipsilateral central lymph nodes,and prelaryngeal lymph node with CLNs.Results: The rates of metastasis to ipsilateral and contralateral central compartments were 73.2% and 23.5%,respectively.In univariate analysis,gender,age,tumor size,multifocality,and thyroiditis were not important in predicting contralateral central compartment lymph node metastasis(P=0.792,0.097,0.531,0.269,1.000,respectively);by contrast,extrathyroidal extension(P=0.017),prelaryngeal lymph nodes(P=0.006),and ipsilateral central lymph nodes(P<0.001)are related to CLN metastasis.However,multivariate analysis showed that ipsilateral central metastasis was an independent risk factor for lymph node metastasis in the contralateral central region when the number of ipsilateral central metastases is ?3(P=0.010).Conclusion: Extracapsular invasion,prelaryngeal lymph nodes,and ipsilateral central lymph node influence the metastases of CLN.Bilateral central lymph node dissection should be performed when the number of ipsilateral central metastases is ?3 and the merger of extra-laryngeal lymph nodes or capsule invasion.