ABSTRACT
Objective To investigate the relationship between subgroups of central lymph node metastasis (sCLNM) and lateral lymph node metastasis (LNM) of unilatal papillary thyroid carcinoma (uPTC) with cervical lymph node negative(cN0).Methods The clinical and pathological data of 161 patients with cN0-uPTC who underwent total thyroidectomy+central lymph node dissection+lateral lymph node dissection from Jan.2016 to Dec.2016 were retrospectively analyzed.The relationship between the lymph node metastasis of each subarea in the central area of the affected side and the lymph node metastasis of the affected side was investigated.Results Binary logistic regression analysis of cN0-uPTC subregions in the affected central region showed:pre-laryngeal lymph node metastasis,pre-tracheal lymph node metastasis and paratracheal lymph node metastasis were independent risk factors for lymph node metastasis in the affected lateral region(P=0.008,0.016,0.035,respectively).Prelaryngeal lymph node metastasis was an independent risk factor for lymph node metastasis in the affected area Ⅱ (P=0.015).Pre-tracheal lymph node metastasis was an independent risk factor for lymph node metastasis in affected area Ⅲ (P=0.004).Pre-tracheal and para-tracheal lymph node metastasis were independent risk factors for lymph node metastasis in the affected Ⅳ area (P=0.035,0.011,respectively).Conclusions The lymph node metastasis pathway of thyroid cancer had certain regularity.The pre-laryngeal lymph node metastasis has the prediction value for the lymph node metastasis of the affected area Ⅱ.The pre-tracheal lymph node metastasis has the prediction value for the lymph node metastasis of the affected area Ⅲ.The pre-tracheal and paratracheal lymph node metastasis have the prediction value for lymph node metastasis of the affected area Ⅳ.Lymph node dissection in affected areas Ⅲ and Ⅳ needs to be considered in patients with pre-tracheal or paratracheal lymph node metastases.On this basis,lymph node dissection on the affected areas Ⅱ,Ⅲ,and Ⅳ might be considered if there is pre-laryngeal lymph node metastasis at the same time.
ABSTRACT
Objective:To analyze the factors related to metastasis of contralateral central lymph node (CLN) in cN0 papillary thyroid car-cinoma (PTC) and discuss the indications for CLN dissection. Methods:We enrolled 149 unilateral PTC patients who underwent total thyroidectomy and prophylactic bilateral (CLN) 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 ip-silateral 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, and 1.000, respectively);by contrast, extrathyroidal extension (P=0.017), prelaryngeal lymph nodes (P=0.006), and ipsilateral CLNs (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 metas-tases is≥3 (P=0.010). Conclusion:Extracapsular invasion, prelaryngeal lymph nodes, and ipsilateral CLN influence the metastases of CLN. Bilateral CLN dissection should be performed when the number of ipsilateral central metastases is≥3 and there is merger of ex-tra-laryngeal lymph nodes or capsule invasion.