A Preliminary Observation Of The Changing Trend Of CtDNA In Patients Receiving EGFR-TKI Adjuvant Therapy For Lung Adenocarcinoma

Objective:To explore the role and value of Circulating tumor DNA in predicting the efficacy of postoperative targeted therapy for lung adenocarcinoma.Methods:Twenty patients who were admitted to the Department of Thoracic Surgery of The Affiliated Hospital of Guizhou Medical University from January 2021 to October2021 with lung adenocarcinoma with clinical stage Ⅰ B - Ⅲ A diagnosed by postoperative pathology were included in this study.All patients received amitinib molecular targeted therapy after surgery,and ctDNA gene detection was performed on peripheral blood of patients before,after surgery and during review by High-throughput sequencing platform of Zhenhe Technology Company.Ct DNA concentration levels and trends of 20 patients before surgery,1 week after surgery,3months after targeted therapy and 6 months after targeted therapy were recorded and analyzed.And 20 patients with lung adenocarcinoma were divided into early and middle stage group of stage ⅠB - Ⅱ and late stage group of stage ⅢA according to their pathological stages.SPSS 20.0 was used for data statistics to analyze the trend of ctDNA concentration levels before surgery,after surgery and after targeted therapy,and to compare the difference of ctDNA concentration between the two groups.The difference was statistically significant if P<0.05Results:Compared with the preoperative ctDNA concentration(5.197±0.744ng/μL)of twenty patients,the postoperative ctDNA concentration of all patients was4.174±1.085ng/μL.The data of 3 months after molecular targeted therapy was3.879±0.792ng/μL and the data of 6 months was 3.750±0.782ng/μL.With the progress of treatment,the concentration of ctDNA in all patients decreased compared with that before surgery.Twenty patients with lung adenocarcinoma were divided into early and middle stageⅠB-Ⅱgroup and late stageⅢA group according to their pathological stages.There were no statistically significant differences in age and gender between 2 groups(P>0.05),and no statistically significant differences in gene mutation types and smoking history between 2 groups(P>0.05).There was no significant difference in the concentration of ctDNA between the two groups before surgery,within 1 week after surgery,3 months after molecular targeted therapy and 6months after treatment(P>0.05).The ctDNA concentration of stageⅢA group was higher than that of stageⅠB-Ⅱgroup within 1 week after surgery,3 and 6months after targeted therapy,and the difference was statistically significant(P<0.05).The concentration of ctDNA in the stageⅠB-Ⅱgroup decreased gradually with the extension of treatment time,and the concentration of ctDNA in 1week after surgery,3 months after targeted therapy and 6 months after surgery was lower than that before surgery,the difference was statistically significant(P<0.05).The concentration of ctDNA in 6 months was lower than that in 1 week after surgery.The difference was statistically significant(P<0.05).Ct DNA concentration in stageⅢA group also decreased gradually with the extension of treatment time.Ct DNA concentration after 3 and 6 months of targeted therapy was also lower than that before surgery,with statistical significance(P<0.05).Ct DNA concentration after 6 months of targeted therapy was lower than that after surgery,with statistical significance(P<0.05).Conclusions:The changing trend of ctDNA concentration is closely related to surgical treatment and molecular targeted therapy.Based on the change of ctDNA concentration level in almonertinib molecular targeted therapy in patients with EGFR-positive lung adenocarcinoma during the treatment process,it can be seen that almonertinib molecular targeted therapy is effective.Similarly,the quantitative analysis of ctDNA has certain application value in the evaluation of the efficacy of adjuvant targeted therapy for lung adenocarcinoma after surgery,which is worthy of further study.