目的 探索甲状腺良性肿瘤行射频消融术(radio frequency ablation,RFA)后结节体积的动态变化,并分析结节再生的危险因素.方法 回顾性收集2019年6月至2021年6期间于岳池县人民医院行RFA治疗的165例甲状腺良性结节患者,根据入院时结节体积的中位数分为小结节体积组(≤15mL,n=116)和大结节体积组(>15mL,n=49).比较2组患者的临床资料及血清学资料;采用多因素Cox比例风险回归模型调整混杂因素后,探索结节初始体积、血管密度及结节位于临界结构附近情况与甲状腺良性结节患者术后结节再生的关系.根据模型构建列线图,采用Bootstrap法抽样验证,采用校准曲线评价模型的校准度,采用受试者工作特征(receiver operating characteristics,ROC)曲线下面积(area under the curve,AUC)评价模型的区分度.结果 小结节体积组的单侧结节占比更高,且术前美容评分、术前症状评分、射频功率、消融时间、总能量、手术时间、术中出血量和住院时间均较低(短),P<0.05.小结节体积组术后的促甲状腺激素(thyroid stimulating hormone,TSH)、游离三碘甲状腺原氨酸(free triiodothyronine,FT3)、过氧化氢酶(catalase,CAT)改变值大于大结节体积组(P<0.05),游离甲状腺素(free thyroxine,FT4)、丙二醛(malondialdehyde,MDA)、超氧化物歧化酶(superoxide dismutase,SOD)、谷胱甘肽过氧化物酶(glutathione peroxidase,GSH-Px)改变值小于大结节体积组(P<0.05).2组患者在RFA术后1、3、6、12、24个月结节体积依次减小,体积缩小率(volume reduction rate,VRR)依次增大;小结节体积组的结节体积及VRR变化均优于大结节体积组.大结节组术后1、3、6、12、24个月的结节体积更大、术后1个月的VRR更高、再生时间更短、残余结节数更多,且初始消融率(initial ablation rate,IAR)较低(P<0.05).调整年龄、性别等因素后,随着初始体积、血管密度的升高,其关联效应值也相应增高,趋势性检验差异均有统计学意义(P趋势<0.05);结节位于临界结构附近者再生风险增高(OR=1.76,P<0.001).根据多因素模型构建的列线图具有较好的区分度(ROC曲线验证前后AUC分别为0.854和0.814)和准确度(平均绝对误差为0.023).结论 RFA在≤15mL和>15 mL单个甲状腺良性结节中均实现了临床相关体积的减小,持续至少2年,但小结节体积组的结节体积缩小率和美容效果更佳.结节初始体积、血管密度及位置与结节再生密切相关,构建的列线图模型在预测结节再生风险方面表现出良好的区分度和准确度,为临床决策提供了有力支持.
Dynamic change of nodule volume after radiofrequency ablation of benign thyroid nodules and its predictive value for nodule regeneration
Objective To investigate the dynamic changes of nodule volume in benign thyroid tumors after radiofrequency ablation(RFA),and to analyze the predictive value of risk factors for nodule regeneration.Methods A total of 165 patients with benign thyroid nodules who received RFA treatment in the People's Hospital ofYuechi County from June 2019 to June 2021 were retrospectively collected and divided into small nodule volume group(≤15 mL,n=116)and large nodule volume group(>15 mL,n=49)according to the median nodule volume at admission.The clinical data and serological data of the two groups were compared.Multivariate Cox proportional hazard regression model was used to adjust confounding factors to explore the relationship between initial nodule volume,vascular density,nodule location near critical structure and postoperative nodule regeneration in patients with benign thyroid nodules.According to the proposed Nomogram of the model,Bootstrap method was adopted for sampling verification,calibration curve was adopted to evaluate the calibration degree of the model,and area under the curve(AUC)of receiver operating characteristics(ROC)curve was adopted to evaluate the model differentiation.Results In the small volume nodule group,the proportion of unilateral nodule was higher,and the preoperative beauty score,preoperative symptom score,radiofrequency power,ablation time,total energy,operative time,intraoperative blood loss and hospital stay were lower or short,P<0.05.The change value of thyroid stimulating hormone(TSH),free triiodothyronine(FT3),catalase(CAT)after operation in small volume nodule group were higher than those in the large nodule volume group(P<0.05),but change value of the free thyroxine(FT4),malondialdehyde(MDA),superoxide dismutase(SOD)and glutathione peroxidase(GSH-Px)were lower than those in the large nodule volume group(P<0.05).At 1,3,6,12,and 24 months after RFA operation,the nodule volume of the two groups decreased successively,and volume reduction rate(VRR)increased successively.The changes of nodule volume and VRR in the small nodule volume group were better than those in the large nodule volume group.In the large nodule group,the nodule volume was larger at 1,3,6,12,and 24 months after operation,and the VRR was higher at 1 month after operation,the regeneration time was shorter,the number of residual nodules was higher,and the initial ablation rate(IAR)was lower(P<0.05).After adjusting for age,gender and other factors,the correlation effect value increased with the increase of initial volume and blood vessel density,and the differences in trend test were statistically significant(Ptrend<0.05).Nodules located near the critical structure had an increased risk of regeneration(OR=1.76,P<0.001).The Nomogram constructed according to the multi-factor model has good differentiation(AUC before and after ROC curve validation were 0.854 and 0.814,respectively)and accuracy(mean absolute error of 0.023).Conclusions RFA achieved clinically relevant volume reduction in both ≤ 15 mL and>15 mL of single benign thyroid nodules,lasting for at least 2 years.However,the nodule VRR and cosmetic effect were better in the small volume nodule group,and the initial nodule volume,blood vessel density and location were closely related to nodule regeneration.The Nomogram model showed good differentiation and accuracy in predicting the risk of nodule regeneration,providing strong support for clinical decision-making.
benign thyroid noduleradio frequency ablationnodule volumedynamic changeclinical significance