Study On The Therapeutic Effect And Related Influencing Factors Of 131I In Patients With Differentiated Thyroid

Objective: To investigate the rate of successful radioactive iodine remnant ablation and adjuvant therapy after thyroidectomy and its influencing factors.Methods:261 patients with DTC were selected from January 2012 to October 2015 in Nuclear Medicine of Affiliated Hospital of Qingdao University Department, 261 patients were treatment with remnant ablation, 57 patients were treatment with adjuvant therapy. Collect clinical information include of the patient’s age, gender, near-total or total thyroidectomy, histological type, with or without Hashimoto thyroiditis(HT)、 tumor diameter, number of foci, unilateral or bilateral foci, TNM stage, risk stratification of recurrence, lymph node and(or) distant metastasis, time between first 131 I therapy and thyroidectomy, dose of 131 I, thyroid stimulating hormone(TSH), stimulated serm thyroglobulin(s Tg, TSH>30m IU/L), thyroglobulin antibody(Tg Ab) before radioactive iodine therapy. Assessment of therapeutic effect and success rate according to “2014 131 I therapy for differentiated thyroid carcer Guide”(Chinese guide) and “2015 American Thyroid Association Management Guidelines for Adult Patientswith Thyroid Nodules and Differentiated Thyroid Cancer”(ATA guide) about 6 months after treatment of radioactive.(1)Assessment of success rate of radioactive iodine remnant ablation and effective rate of adjuvant therapy.(2)Analyzing whether above mentioned factors are difference between successful and unsuccessful remnant ablation groups, effective and ineffective adjuvant therapy groups.(3)Discusssing the predictive value of preablation s Tg, s Tg/TSH ratio and tumor diameter in the effect of radioactive iodine remnant ablation,the predictive value of s Tg, s Tg/TSH ratio and tumor diameter in the effect of radioactive iodine adjuvant therapy.Results:(1) The successful rate of radioactive iodine remnant ablation is 65.90%(172/261).(2)Singel factor analysis shower that tumor diameter,preablation s Tg are lower in successful radioactive iodine remnant ablation groop than unsuccessful groop(all P<0.05); the successful iodine remnant ablation rate of low, intermediate and high risk of recurrence groups are 91.67%、66.37%、60.48%, respectively, the successful rate is higher in low risk of recurrence group than intermediate and high risk of recurrence groups(all P<0.017); the successful rate in without metastasis group, postoperative without metastasis group, lymph node metastasis group and distant metastasis group are 92.5%, 69.17%, 47.37% and 50.00% respectively, the success rate in without metastasis group is higher than that three groups(all P < 0.008); there are no difference between age,gender, near-total or total thyroidectomy, histological type, with or without HT, number of foci, unilateral or bilateral foci, TNM stage, time between first 131 I therapy and thyroidectomy, dose of 131 I, TSH level, in the patients with successful ablation and unsuccessful ablation(all P>0.05).(3)The regression equation predicting the effect of radioactive iodine remnant ablation is logit(P)=3.494-0.465*tumor diameter-0.002*s Tg-2.244* lymph node metastasis group-1.585*ditant metastases.(4)The areas under ROC for s Tg, s Tg/TSH ratio and tumor diameter to predict unsuccessful ablation are 0.831, 0.824, 0.648 respectively, cutoff value are 4.595ng/ml, 0.046mg/IU and 1.35 cm, respectively; the sensitivity are 95.51%, 96.63%, 73.03%, respectively; the specificity are 64.54%, 61.63%, 49.41%, respectively.(5)57 DTC patients undergoing radioactive iodine treatment of metastatic disease, the effective rate is 77.19%(44/57); the efficiency of radioactive iodine treatment of the lymph node metastasis groop is higher than distant metastasis groop(88.57%VS59.09%, P<0.01); tumor diameter, s Tg levels and s Tg/TSH ration are lower in effiecacy groop than ineffiecacy groop(all P<0.05); there are no difference between age, genter, histological type, TSH level and whether the first 131 I whole body scan positive or negative in the patients with effiecacy groop than ineffiecacy groop(all P>0.05).(6)The regression equation predicting the effect of radioactive iodine therapy with metastasis is logit(P)=4.047-0.717*tumor diameter-0.007*s Tg.(7)The areas under ROC for s Tg, s Tg/TSH ratio, tumor diameter predictive to effect of adjuvant therapy are 0.856, 0.861, 0.722, respectively; cutoff value are 32.61ng/ml, 0.32mg/IU, 3.9cm, respectively; the sensitivity are 92.31%, 92.31%, 46.15%, respectively; the specificity are 63.63%, 61.37%, 88.64%, respectively.Conclusions:(1)The successful rate of radioactive iodine remnant ablation is 65.90%(172/261), the effective rate of radioactive iodine treatment of metastatic disease is 77.19%(44/57).(2)Tumor diameter, preablation s Tg levels, lymph node and(or) distant metastasis are effect factors for ablation of remnant thyroid.(3)Preablation s Tg, s Tg/TSH ratio are predictive markers for the effect of remnant ablation.(4)Tumor diameter, metastasis sites, s Tg levels are factors that affect the efficacy of radioactive iodine treatment of metastatic disease.