The Value Of Risk Scoring Model Combined With FNAC For Diagnosis Of Microscopic Thyroid Nodular Papillary Carcinoma

AIM:To investigate the diagnostic value of risk scoring model combined with ultrasound-guided thyroid nodule fine needle aspiration cytology(FNAC)in the diagnosis of microscopic thyroid nodular papillary carcinoma.METHODS:A retrospective analysis was performed on 171 patients who underwent thyroid nodule fine needle aspiration cytology in the department of endocrinology of our hospital from April 2016 to July 2018.collect Basic information of the patients(age,gender,height,weight);previous medical history(family genetic history,radiation exposure history,type 2 diabetes history);serological indexes(TSH,Tg Ab);imaging and pathological results(ultrasonic report,FNAC pathological report,surgical pathology report).The above indexes were collected for assignment,calculate the score of each microscopic nodules,build risk scoring model(in the high-risk group of 4 to 7 points,dangerous groups of 8 to 11 points,low-risk group of 12 to 15 points).respectively drawn TI-RADS and risk scoring model predict the ROC curve of benign and malignant microscopic thyroid nodules,prediction of ROC curve,calculating the area under the curve(AUC)and cut-off point value.The cut-off point value was used as the criterion to determine the benign and malignant microscopic thyroid nodules,can calculate the degree of the sensitivity of the two methods of diagnosis,specific,accuracy,positive predictive value and negative predictive value.?~2 test was used for comparison between groups,and Z test was used for comparison of AUC values.P<0.05 was considered statistically significant.The risk scoring model and FNAC results were used to establish a Logistic regression analysis model to compare the accuracy of risk scoring model,FNAC and their combined diagnosis.RESULTS:The ROC curve of TI-RADS for predicting the risk of microscopic nodules suggested that the optimal cut-off point was between 4a and 4b,and the area under the curve,sensitivity,specificity,accuracy,positive predictive value and negative predictive value were 79.0%(95%confidence interval 0.707-0.873),85.7%,69.1%,72.5%,41.6%and 94.9%.The ROC curve of the risk score model for predicting the risk of microscopic nodules suggested that the optimal cut-off point was 8,and the area under the curve,sensitivity,specificity,accuracy,positive predictive value and negative predictive value were 94.2%(95%confidence interval 0.900-0.984),85.7%,91.2%,90.0%,71.4%and96.1%.The?~2 test was applied between the groups,showing that the specificity,accuracy and positive predictive value of the risk scoring model were significantly higher than that of the TI-RADS(?~2=23.904,26.535,9.452.P<0.05),but the sensitivity and negative predictive values were not statistically significant(?~2=0.000,0.184.P>0.05).The AUC of the risk scoring model was significantly higher than that of the TI-RADS(Z=3.040.P<0.05).The sensitivity,specificity,accuracy,positive predictive value and negative predictive value of FNAC in the diagnosis of papillary thyroid microcarcinoma were71.8%,94.7%,89.5%,80.0%and 91.9%.After the binary Logistic regression analysis of the risk scoring model and FNAC,the regression equation Logistic(P)=0.810×scoring model+2.522×FNAC-9.026 was obtained.In the regression equation,when regression value>0.5,it was predicted to be papillary thyroid microcarcinoma,and when regression value?0.5,it was predicted to be benign thyroid microscopic nodules.computing the sensitivity,specificity,accuracy,positive predictive value and negative predictive value of FNAC combined risk scoring model in the diagnosis of papillary thyroid microcarcinoma were 87.1%,94.3%,93.0%,77.1%,97.1%,were higher than any single diagnostic accuracy.CONCLUSION:This study confirmed that the risk scoring model established based on Basic information of the patients,previous medical history,serological indexes,imaging and pathological results.which has higher accuracy and specificity than TI-RADS,which is helpful for the diagnosis of benign and malignant microscopic thyroid nodules.Risk scoring model combined with FNAC can improve the predictive accuracy of papillary thyroid microcarcinoma and reduce clinical over treatment.