The Value Of BRAF,TERT Gene Mutation Detection Based On Fine Needle Aspiration In Predicting The Malignant Degree Of Papillary Thyroid Carcinoma Before Operation

Background:the treatment and comprehensive management of thyroid cancer are controversial.More accurate preoperative assessment and risk stratification are the main research directions in the future;the value of fine needle aspiration specimen combined with BRAF gene and TERT gene mutation in predicting thyroid papillary carcinoma before operation is still controversial,and reasonable aspiration,sampling and detection methods are still unclear.Objective:the purpose of this study was to explore the value of fine needle aspiration combined with BRAF gene and TERT gene mutation in predicting the malignant degree of papillary thyroid carcinoma from the aspects of aspiration,sampling and detection methods,and detection of molecular markers,to provide more comprehensive diagnostic information for clinical decision-making before operation.Study design:single-center prospective cohort study,single-center retrospective case-control studyPatients:Patients involved in part one were chosen from March 2018 to October 2018,patients who came to our department of ultrasound for thyroid nodules were diagnosed by ultrasound doctors as requiring fine needle aspiration of thyroid nodules,rom March 2018 to October 2018.Patients involved in part two and part three were chosen from patients accepted ultrasound guided aspiration and thyroidectomy in Shanghai sixth people's Hospital between January 1,2016 and June 30,2018.Patients whose result of operation pathology was thyroid papillary carcinoma and the aspiration samples were well preserved and were checked by pathologists to meet the diagnostic criteria;Patients whose surgical tissue were examined for the V600E mutation in the BRAF gene.Methods:Kruskal-Wallis test was used to analyze the time required for different aspiration methods in part one.Both univariable and multivariable analysis were performed to analyze the impact of different aspiration methods on outcome indicators in part one.Paired chi-square test,consistency test were performed to compare the diagnostic sensitivity and specificity of different detection methods in part two.T-test,chi-square test was used to analyze the relationship between the two gene mutations and outcome index,and paired Chi-square test was used to analyze the difference of sensitivity and specificity between the two gene mutations in part three.Results:Of 100 patients involved in part one study,the average and median time of aspiration was 27 seconds and 23 seconds in method 1(needle+empty syringe+capillary action);31 seconds and 29 seconds in method 2(needle+syringe with piston+capillary action);28 seconds and 25 seconds in method 3(needle+syringe with piston+negative pressure suction).The average time of the first method was the shortest,this difference was statistically different(p=0.04).Different aspiration methods had no effect on the decrease of the satisfaction degree of aspiration sampling,p=0.78.The age?45 years,the maximum diameter of nodules ?8 mm,and the easily bleeding of nodules were the independent risk factors for the decrease of the satisfaction degree of aspiration sampling(p<0.05).The independent risk factors for non-conformable aspiration diagnosis were method 2(needle+syringe with piston+capillary action)and easily bleeding of nodules(p<0.05).Of 108 nodules involved in part two,the DNA samples were successfully extracted by scraping staining,the minimum concentration was 2.6 ng/?l,and the OD ratio of all samples met the requirement of purity of DNA.Of 40 nodules whose surgical tissue were examined for the V600E mutation in the BRAF gene,the sensitivity of ARMS-PCR and Sanger sequencing were 100%and 97.2%,the specificity were both 100%.The difference between the above results was not statistically significant.The mutation rate of BRAF V600E was 75%in 44 samples,and there was no significant correlation between the mutation and the index of malignant degree of papillary thyroid carcinoma and TNM stage.The mutation rate of TERT promoter was 29.5%,and the mutation was related to the age? 45 years old,the invasion of extra-thyroid tissue,the invasion of thyroid capsule,and the high malignant degree(TNM stage:? stage or ?stage)of the tumor.The combined mutation rate was 25%,which was associated with the larger diameter of nodules,age? 45 years,invasion of extra thyroid tissue,invasion of thyroid capsule,and high malignant degree of tumor(TNM stage ? or ? stage).The sensitivity,specificity of TERT promoter mutation and BRAF V600E mutation prediction were 80%,80%and 27.6%,96.6%,respectively(p<0.01).The sensitivity and specificity of combined mutation prediction were 73.3%and 100%respectively.Conclusion:The three different methods:needle+ empty syringe+capillary action;needle+syringe with piston+capillary action;needle+syringe with piston+negative pressure suction have no effect on the satisfaction degree of the needle aspiration sampling of the thyroid nodules.The needle+empty syringe+capillary action method requires a short time to aspiration,and the needle+ syringe with piston+ capillary action will cause the risk of non-compliance of the puncture diagnosis to rise.The method can effectively extract high-quality DNA samples by scraping the stained smear target cell method,and the ARMS-PCR method can accurately detect the specific gene mutation of the fine needle aspiration cytological sample.The detection of the single TERT promoter mutation,single BRAF gene V600E mutation and the combined detection of these two mutations along with thyroid fine needle aspiration has high application value in predicting the malignant degree of the thyroid papillary carcinoma before the operation.