动态监测^(131)I治疗前刺激性Tg在DTC远处转移诊治中的增益效应

The Incremental Effect of Dynamically Tracing Pre-ablation Stimulated Thyroglobulin in the Diagnosis and Treatment for Distant Metastasis in Differentiated Thyroid Cancer

[目的]探讨动态监测131I治疗前刺激性甲状腺球蛋白(s Tg)在伴有远处转移的分化型甲状腺癌(DTC)诊治中的意义。[方法]221例甲状腺全切或次全切术后拟行131I治疗的DTC患者,根据是否存在远处转移分为M1组(50例)和M0组(171例)。动态监测131I治疗前s Tg及相应促甲状腺激素(TSH)水平(首次测量值记为Tg1、TSH1,末次记为Tg2、TSH2)。分别计算s Tg变化值(△Tg)及其变化速度(v Tg)、Tg/TSH变化值(△Tg’)及其变化速度(v Tg’),以及s Tg随TSH变化比值(△Tg/△TSH)。将以上各s Tg变化指标分别与Tg1、Tg2结合,建立Logistic回归方程,并用ROC曲线及最佳诊断界值点(DCP)评估各指标单独及联合应用在判断远处转移性DTC的价值。[结果]s Tg变化指标中,△Tg/△TSH对远处转移性DTC的诊断更有价值,界值范围为-0.40~0.44ng/μIU,对应灵敏度、特异性、准确率分别为90.00%、88.89%和89.14%。△Tg/△TSH结合s Tg水平(Tg1或Tg2)联合判断DTC远处转移的ROC曲线下面积(AUC)可达0.971,特异性93.57%,准确率92.31%,较两者单独应用时均有提高。[结论 ]131I治疗前动态监测s Tg对伴有远处转移DTC的诊疗具有增益效应,s Tg随TSH变化比值(△Tg/△TSH)与s Tg水平结合有助于提高DTC远处转移诊断的准确率和特异性,为DTC 131I治疗前评估及治疗策略的制定提供依据。

[Purpose] To investigate the value of dynamically tracing pre-ablation stimulated thyroglobulin（s Tg） in the diagnosis and treatment for differentiated thyroid cancer（DTC） with distant metastasis. [Methods] The 221 cases with DTC undergoing total or subtotal thyroidectomy were divided into 2 groups：M1（n=50） and M0（n=171） according to the presence or absence of distant metastases. Pre-ablation s Tg and the corresponding thyroid stimulating hormone（TSH） values were dynamically surveilled. The pre-ablation s Tg and corresponding TSH collected at the first time were marked as Tg1 and TSH1,while as Tg2 and TSH2 at the last time. Variation indexes including pre-ablation s Tg variation（ΔTg） and its velocity（v Tg）,Tg/TSH variation（ΔTg＇） and its velocity（v Tg＇）,as well as ΔTg/ΔTSH ratio were calculated. Logistic regression equation was established based on the above variation indexes combining with Tg1 and Tg2,respectively. All of the indexes,independent or combined were compared by receiver operating characteristic（ROC）curves and diagnostic critical point（DCP） to evaluate their value in judging distant metastasis of DTC. [Results] Among all of the s Tg variation indexes,ΔTg/ΔTSH,whose reference range was-0.40~0.44ng/μIU,worked best in judging distant metastasis of DTC with sensitivity of 90.00%,specificity of 88.89%,and accuracy of 89.14%. The area under the ROC curve of ΔTg/ΔTSH combining with either of pre-ablation s Tg（Tg1 or Tg2） in judging distant metastasis was 0.971.This combination,compared with each of the independent indexes,helped improve the accuracy to 92.31% with a higher specificity（93.57%）. [Conclusions] Dynamically tracing s Tg before radioiodine therapy might offer more incremental effect to the diagnosis and treatment for distantmetastasis in DTC. Combining ΔTg/ΔTSH with either of pre-ablation s Tg（Tg1 or Tg2） would be helpfull to improve the accuracy and specificity of judging distant metastasis in DTC patients as well as providing evidence for pre-ablative assessment and strategies of radioiodine treatment.