甲状腺乳头状癌^131I清甲治疗前后刺激性甲状腺球蛋白对清甲疗效的预测价值

Predictive value of the stimulated thyroglobulin before and after ^131I therapy for curative effect in patients with papillary thyroid carcinoma

目的分析甲状腺乳头状癌（PTC）患者131I清除残留甲状腺组织（简称清甲）治疗前后刺激性甲状腺球蛋白（sTg）水平、变化趋势及其对清甲疗效的预测价值。方法纳入2013年1月至2016年9月在天津医科大学总医院接受131I治疗的178例PTC患者，其中男53例，女125例，年龄（44.1±11.4）岁。根据清甲后6个月^131I-WBS结果，分为有甲状腺组织残留组（简称残留组；23例）和无残留组（155例），分别记录131I治疗前促甲状腺激素（TSH）及sTg（TSH1、sTg1），^131I治疗后TSH及sTg（TSH2、sTg2），采用两样本t检验、χ^2检验和Mann-Whitney u检验比较2组间差异，通过受试者工作特征（ROC）曲线和最佳诊断界值点（DCP）评估sTg对清甲疗效的预测价值。结果2组患者在年龄（t=1.007）、性别（χ^2=1.419）、癌灶最大径（u=1 385）、多灶（χ^2=0.371）、腺外侵犯（χ^2=0.020）、淋巴结转移（χ2=0.391）等方面，差异均无统计学意义（均P〉0.05）。残留组sTg1和sTg2分别为6.3（2.0，16.9）和1.7（0.8，4.2） μg/L，高于无残留组的2.7（0.6，6.4）和0.3（0.2，1.3） μg/L（u=1 118.5、817.0，均P〈0.01）；2组间ΔsTg与ΔsTg/ΔTSH差异均无统计学意义（u=1 359.5、1 195.0，均P〉0.05）。sTg1的ROC曲线下面积、DCP、灵敏度、特异性、阳性预测值和阴性预测值分别为0.686、4.435 μg/L、60.9%（14/23）、67.7%（105/155）、21.9%（14/64）、92.1%（105/144）；sTg2的相应值分别为0.771、0.460 μg/L、91.3%（21/23）、58.1%（90/155）、24.4%（21/86）、97.8%（90/92）。结论PTC患者131I清甲治疗前后sTg有助于预测131I清甲疗效，清甲治疗前sTg1〈4.435 μg/L预示单次清甲疗效较好，清甲治疗后sTg2〈0.460 μg/L往往预示清甲成功。

Objective To analyze the stimulated thyroglobulin （sTg） level and variation tendency before and after 131I therapy in papillary thyroid carcinoma （PTC）, and evaluate the predictive value of sTg for the efficacy of 131I therapy.Methods From January 2013 to September 2016, a total of 178 PTC patients （53 males, 125 females; average age （44.1±11.4） years） without distant metastases who received ^131I treatment in Tianjin Medical University General Hospital were reviewed. The patients were divided into two groups： group 1 （n=23） with residual thyroid detected by 131I whole body scan （WBS） and group 2 （n=155） without residual thyroid. Both thyroid stimulating hormone （TSH） and sTg were measured and defined as TSH1, sTg1 before ^131I therapy, and TSH2, sTg2 after 131I therapy. Data of the two groups were compared with two-sample t test, χ^2 test and Mann-Whitney u test. The receiver operating characteristic （ROC） curve and diagnostic critical point （DCP） were used to evaluate the predictive value of sTg in radioiodine ablation efficacy.Results There were no significant differences in age （t=1.007）, gender （χ^2=1.419）, tumor diameter （u=1 385）, multifocal cancer （χ^2=0.371）, extrathyroidal extension （χ^2=0.020） or lymph node metastasis （χ^2=0.391, all P〉0.05） between group 1 and group 2. The levels of sTg1 and sTg2 of group 1 were 6.3（2.0, 16.9） and 1.7（0.8, 4.2） μg/L, which were higher than those of group 2 （2.7（0.6, 6.4） and 0.3（0.2, 1.3） μg/L; u=1 118.5, 817.0, both P〈0.01）. ΔsTg and ΔsTg/ΔTSH showed no statistical differences between the two groups （u=1 359.5, 1 195.0, both P〉0.05）. The area under ROC curve, DCP, sensitivity, specificity, positive predictive value, and negative predictive value of sTg1 were 0.686, 4.435 μg/L, 60.9%（14/23）, 67.7%（105/155）, 21.9% （14/64） and 92.1%（105/144）, respectively. Meanwhile, the parameters of sTg2 were 0.771, 0.460 μg/L, 91.3%（21/23）, 58.1%（90/155）, 24.4%（21/86） and 97.8%（90/92）, respectively.Conclusions The level of sTg could be used to predict the efficacy of 131I therapy in PTC patients. Preablative sTg1 （〈4.435 μg/L） or postablative sTg2 （〈0.460 μg/L） holds high negative predictive value in identifying the efficacy of single 131I therapy.