Table_1_Risk Factors and a Prediction Model of Lateral Lymph Node Metastasis in CN0 Papillary Thyroid Carcinoma Patients With 1–2 Central Lymph Node Metastases.docx

BackgroundPapillary thyroid cancer (PTC) in clinically lymph node-negative (cN0) patients is prone toward lymph node metastasis. As a risk factor for tumor persistence and local recurrence, lateral lymph node metastasis (LLNM) is related to the number of central lymph node metastases (CLNMs). MethodsWe performed LLNM risk stratification based on the number of CLNMs for cN0 PTC patients who underwent thyroidectomy and lymph node dissection between January 2013 and December 2018. A retrospective analysis was applied to the 274 collected patients with 1-2 CLNMs. We examined the clinicopathological characteristics of the patients and constructed a LASSO model. ResultsIn the 1–2 CLNM group, tumors >10 mm located in the upper region and nodular goiters were independent risk factors for LLNM. Specifically, tumors >20 mm and located in the upper region contributed to metastasis risk at level II. Hashimoto’s thyroiditis reduced this risk (p = 0.045, OR = 0.280). Age ≤ 30 years and calcification (microcalcification within thyroid nodules) correlated with LLNM. The LASSO model divided the population into low- (25.74%) and high-risk (57.25%) groups for LLNM, with an AUC of 0.715. ConclusionsFor patients with 1–2 CLNMs, young age, calcification, nodular goiter, tumor >10 mm, and tumor in the upper region should alert clinicians to considering a higher occult LLNM burden. Close follow-up and therapy adjustment may be warranted for high-risk patients.背景 临床淋巴结阴性（clinically lymph node-negative, cN0）的甲状腺乳头状癌（Papillary Thyroid Cancer, PTC）患者极易发生淋巴结转移。侧方淋巴结转移（Lateral Lymph Node Metastasis, LLNM）作为肿瘤持续存在与局部复发的危险因素，与中央区淋巴结转移（Central Lymph Node Metastases, CLNMs）的数量密切相关。 方法 本研究针对2013年1月至2018年12月期间接受甲状腺切除术及淋巴结清扫术的临床淋巴结阴性（cN0）甲状腺乳头状癌（PTC）患者，基于中央区淋巴结转移（CLNMs）数量进行侧方淋巴结转移（LLNM）风险分层。本研究对收集的274例中央区淋巴结转移数为1~2枚的患者开展回顾性分析，评估患者的临床病理特征，并构建LASSO（Least Absolute Shrinkage and Selection Operator）模型。 结果 在中央区淋巴结转移数为1~2枚的患者亚组中，肿瘤直径＞10mm且位于甲状腺上极、合并结节性甲状腺肿是侧方淋巴结转移（LLNM）的独立危险因素。具体而言，肿瘤直径＞20mm且位于甲状腺上极会增加Ⅱ区淋巴结转移风险；桥本甲状腺炎（Hashimoto’s Thyroiditis）可降低该风险（p = 0.045, OR = 0.280）。年龄≤30岁及甲状腺结节微钙化（microcalcification within thyroid nodules）与LLNM显著相关。LASSO模型将研究人群划分为侧方淋巴结转移低风险组（25.74%）与高风险组（57.25%），受试者工作特征曲线下面积（Area Under the Curve, AUC）为0.715。 结论 对于中央区淋巴结转移数为1~2枚的甲状腺乳头状癌（PTC）患者，年龄较轻、甲状腺结节钙化、合并结节性甲状腺肿、肿瘤直径＞10mm以及肿瘤位于甲状腺上极，均提示临床医师需警惕患者存在更高的隐匿性侧方淋巴结转移（LLNM）负荷。对于高风险人群，应加强随访并调整治疗方案。