Dynamic changes of thyroglobulin antibody and its prognostic value for papillary thyroid carcinoma / 中华核医学与分子影像杂志

ABSTRACT

Objective To investigate the change of thyroglobulin antibody (TgAb) level in patients with TgAb-positive papillary thyroid carcinoma (PTC),and explore the relationship between the variation of TgAb level and prognosis.Methods A total of 817 PTC postoperative patients (254 males,563 females,median age 45 years) who underwent radioactive iodine therapy (RAI) from February 2008 to December 2014 were retrospectively analyzed.There were 130 patients with TgAb (+),and 687 patients with TgAb (-).The dynamic changes of TgAb in 3 years after RAI were observed,and the threshold value of TgAb reduction rate in predicting recurrence/metastasis was plotted.Mann-Whitney u test,x2 test and receiver operating characteristic(ROC) curve analysis were used to analyze the data.Results There were statistically significant differences in gender,concurrent with Hashimoto thyroiditis (HT),risk stratification and recurrence/metastasis between TgAb (+) and TgAb (-) groups (x2 values13.988-191.059,z =2.053,all P＜0.05).There were statistically significant differences in tumor size,extrathyroidal extension,risk stratification,TgAb before RAI and concurrent with HT between TgAb (+) patients with and without recurrence/metastasis (x2 values3.865-6.278;z values4.624,3.641,all P＜0.05).There were statistically significant differences in tumor size,extrathyroidal extension,risk stratification and TNM staging between TgAb (-) patients with and without recurrence/metastasis (x2 values13.459,8.215,z values5.385,3.998;all P＜0.05).For patients with TgAb (+),the optimum cut-off threshold of TgAb reduction rate in predicting recurrence/metastasis by ROC curve analysis at 1,2 and 3 years after RAI was 54.0％,38.0％ and 59.0％,respectively,and the corresponding area under the curve (AUC) was 0.847,0.815 and 0.822,respectively.Conclusions The trend of the TgAb after RAI is related to the prognosis of patients.Patients with TgAb decreased ≥54.0％,≥38.0％,≥59.0％ after 1,2,3 years post-RAI may have better prognosis.