甲状腺乳头状癌淋巴结转移率与131I 治疗后临床转归的关系

背景与目的：甲状腺乳头状癌(papillary thyroid carcinoma，PTC)常伴淋巴结转移，该研究旨在探讨PTC患者的淋巴结转移率(lymph node metastatic rate，LR，即转移淋巴结数/切除淋巴结总数)与经131I清甲治疗后临床转归的关系及其预测价值。方法：随访PTC患者143例，根据LR将其分为Ⅰ组(0～10%，n=22)、Ⅱ组(10%～25%，n=51)、Ⅲ组(25%～50%，n=52)和Ⅳ组(>50%，n=18)，经过131I清甲治疗后20.7个月的中位随访，根据2015年美国甲状腺协会指南的治疗反应将患者的临床转归分为：满意(excellent response，ER)、不确切(indeterminate response，IDR)和反应欠佳血清学反映欠佳(biochemical incomplete response，BIR)、影像学反应欠佳(structural incomplete response，SIR)]，采用单因素方差分析、χ2检验和Kruskal-Wallis秩和检验比较4组患者的基本临床特征和临床转归；应用受试者工作特征(receiver operating characteristic，ROC)曲线评估LR在预测ER的价值及最佳界值点，并进一步通过多因素分析评估LR是否可以作为预测ER的独立因素。结果：4组患者的性别、肿瘤T分期差异无统计学意义(P均＞0.05)，Ⅰ组年龄显著高于其他3组(F=6.114，P=0.001)。随LR增高，临床转归达到ER者呈下降趋势，同时BIR及SIR者总体呈升高趋势。其中，Ⅳ组的治疗反应ER率明显低于其他3组(27.8%)，而更易呈现为BIR(27.8%)和SIR(11.1%)(H=18.816，P=0.000)。LR可以作为预测ER的独立因素(OR=10.011，P=0.000)，当其为52.27%时对预测ER具有较高特异性(95.09%)，ROC曲线下面积为0.668(P=0.002)。结论：随LR增高患者131I清甲治疗后更易出现较差的临床转归，LR为52.27%的界值点可作为预测临床转归的独立特异性指标。

The impact of lymph node metastatic rate on clinical outcome following131I therapy in patients with papillary thyroid carcinoma

Background and purpose:This study aimed to investigate the relationship between lymph node metastatic rate (LR) and response to radioiodine therapy in patients with papillary thyroid carcinoma (PTC).Methods:A total number of 143 PTC patients after radioiodine therapy were included and classified into 4 groups Ⅰ(0%-10%),Ⅱ(>10%-25%),Ⅲ(>25%-50%),Ⅳ(>50%)] according to the lymph node metastatic rate, and the responses to initial radioiodine therapy after a median follow-up period of 20.7 months were evaluated. They were classiifed into 4 groups excellent response (ER), indeterminate response (IDR), biochemical incomplete response (BIR), and struc-tural incomplete response (SIR)] according to the guideline proposed by 2015 American Thyroid Association. One-Way analysis of variance,χ2 test and Kruskal-Wallis test were used to evaluate the differences in basic clinicopathological features and clinical responses among the 4 groups. The ROC curve was analyzed to evaluate the clinical value of lymph node metastatic rate for predicting ER and optimal cut-off point.Results:There were no signiifcant differences in gender and T-stage among 4 groups (P>0.05). However,Ⅰ group was signiifcantly older than the other 3 groups (P=0.001). With the increase of lymph node metastatic rate, the number of ER cases decreased, while cases of BIR and SIR generally increased. Compared with the other 3 groups, less cases of ER (27.8%), while more BIR (27.8%) or SIR (11.1%) were observed in groupⅣ (H=18.816,P=0.000). Cut-off value of lymph node involved rate was 52.27%, with a better speciifcity of predicting ER. Area under the ROC curve was 0.668.Conclusion:The higher lymph node metastatic rate in patients with PTC, the worse clinical outcome it could be. A cut-off value of lymph node metastatic rate 52.27% is a speciifc independent predictor for the clinical outcome in PTC patients treated with radioiodine therapy.