RESUMO
Objective To explore the lateral neck lymph node metastasis (LNM) in patients affected by papillary thyroid carcinoma(PTC) with clinically negative neck (cN0-PTC) and to discuss the necessity of prophylactic lateral neck lymph node dissection.Methods Clinical data of 651 cN0-PTC patients who underwnt surgical procedure in Tumor Hospital of Zhengzhou University from Jan.2012 to May.2015 were retrospectively analyzed.Chi-square test was used for univariate analysis.Results Of the 651 cN0-PTC patients,62.9％ had LNM (51.3％ in central neck,41.0％ in lateral neck,and 11.7％ with "skip" metastasis).The lateral neck metastasis rate was 50.9％ in men and 37.7％ in women (P＜0.05),61.9％ in patients with tumor diameter ＞1.0 cm and 25.9％ in patients with tumor diameter ≤ 1.0 cm (P＜0.001),47.2％ with multifocal cancer and 40.3％ with unifocal tumor(P＜0.05),63.1％ with extrathyroidal extention and 34.3％ without extention (P＜0.001),64.1％ with ≥3 positive nodes in central neck and 48.3％ with ＜3 positive nodes (P＜0.05),52.4％ with upper lobe cancer and 32.9％ with other locations(P＜0.001),41.0％ in patients ≤45 years and 40.9％ in patients ＞45 years(P＞0.05).Conclusion Central neck dissection should be performed in all cN0-PTC patients.Prophylactic lateral neck dissection should beselectively performed in cN0-PTC patients with following high-risk factors:male,tumor diameter ＞1.0 cm,multifocal cancer,extrathyroidal extention,≥ 3 positive nodes in central neck and upper lobe cancer.