Clinical Comparative Studies Of CT-guided Percutaneous Microwave Ablation And Thoracoscopic Sublobar Resection For Pulmonary Ground-glass Nodules

Background The detection rate of ground-glass nodules(GGN)is gradually increasing,which is the manifestation of early lung cancer.Surgical resection is the "gold standard" for malignant pulmonary nodules,but some patients are unable to tolerate or unwilling to undergo surgery due to poor cardiopulmonary function or other reasons.Microwave ablation(MWA)has the advantages of high safety and definite efficacy in treatment of pulmonary nodules,it becomes a hot research topic in the field of lung cancer treatment.Objective The purpose of this study is to explore the safety,effectiveness and cost of CT-guided percutaneous MWA and thoracoscopic sublobar resection in the treatment of GGN.Methods This study adopts a retrospective analysis.By selecting the GGN patients who underwent CT-guided percutaneous MWA or thoracoscopic sublobar resection in Yichang Central People’s Hospital from May 2020 to May 2022 as the study subjects,they were divided into MWA group(40 cases in total,18 cases of CT-guided MWA synchronous pathological biopsy,22 cases of simple MWA)and sublobar resection group(150 cases in total,hereinafter referred to as SLR group)depending on the different treatment methods.The basic information,surgical related data,pathological data and postoperative follow-up data of the two groups were collected to evaluate the overall survival(OS),recurrence-free survival(RFS),local control rate,complications,hospital stay and cost.Kaplan-Meier method was used to construct survival curves and log-rank test was used for comparison.Results(1)In terms of baseline data,the gender,GGN type,location and image characteristics of the two groups were not statistically significant(P>0.05).The median age(65.5 vs 53.5 years old,P<0.001)and median GGN diameter(1.3 vs 1.0 cm,P=0.001)of the MWA group were significantly worse than those of the SLR group,the differences were statistically significant.(2)The technical success rate of both groups was 100%,and there was no operative related death.In terms of the incidence of complications,pneumothorax was the most common complication of MWA.Among the 40 cases of MWA,11 cases(27.5%,11/40)occurred pneumothorax,only 4 cases needed closed thoracic drainage.The incidence of pneumothorax in the SLR group was 35.3%(53/150).There was no statistical difference between the two groups(P=0.352).Other complications of MWA included fever(2.5%,1/40),postoperative pain(12.5%,5/40)and pleural effusion(2.5%,1/40).The incidence of pleural effusion in SLR group was 34.7%(52/150),which was significantly different from that in MWA group(P<0.001).Other complications in SLR group included fever(2.5%,3/160),postoperative pain(12%,8/150),pneumonia(5.3%,8/150),postoperative atelectasis(10.7%,16/150),air leakage(1.3%,2/150)and bleeding(2%,3/150),the differences were not statistically significant(P>0.05).(3)In terms of lesion clearance rate,the lesions in MWA group were completely ablated,and the lesions in SLR group were completely removed.There was no significant difference between the two groups(P>0.05).(4)In terms of operation related data,the median operation time(65 vs 100 min,P<0.05),median intraoperative bleeding(5 vs 20 ml,P<0.05),median postoperative hospital stay(2.5 vs 5 days,P<0.05)and hospital expenses(13.9 vs 28.6 thousand,P<0.05)in MWA group were significantly lower than those in SLR group,the differences were statistically significant.(5)In terms of pathological results,only 45%(18/40)of patients in MWA group agreed to undergo MWA synchronous pathological biopsy,and the remaining 55%(22/40)of patients underwent simple MWA.Among these 18 cases,72.2%(13/18)were diagnosed as adenocarcinoma,11.1%(2/18)as atypical adenomatous hyperplasia and 16.7%(3/40)as benign lesions.150 patients in SLR group were analyzed.Among these 150 cases,90.6%(136/150)were diagnosed as adenocarcinoma,4.7%(7/40)as atypical adenomatous hyperplasia and 4.7%(7/40)as benign lesions,all patients had no lymph node metastasis.The positive diagnosis rates of two groups were 83.3%(15/18)and 95.3%(143/150)respectively,the difference was not statistically significant(P=0.056).(6)In terms of survival results,the median follow-up time of MWA group was 15months(range 10～34).During the follow-up period,40 patients had no local tumor progression and tumor recurrence.The overall survival rate of one-year and two-year were97.5% and 97.5%,and the one-year and two-year recurrence-free survival rate were 100%and 100%,respectively.The median follow-up time of the SLR group was 16 months(range9～34).The overall survival rate of one-year and two-year were 100% and 100%,and the recurrence-free survival rate of one-year and two-year were 99.3% and 99.3%,respectively.There were no statistical significance between the one-year and two-year OS rates(P=0.053)and the RFS rates(P=0.606)of two groups.Conclusion CT-guided percutaneous MWA is a safe and effective modality for GGN.From the current results,the MWA group has similar 1-year and 2-year OS and RFS compared to sublobar resection,with fewer complications,lower bleeding volume,and more advantages in terms of hospital costs.MWA should be considered as an effective alternative treatment for GGN patients with severe cardiopulmonary comorbidity,which causes intolerance of surgery or general anesthesia with tracheal intubation,and in patients unwilling to undergo surgery.However,this conclusion needs to be further confirmed by prospective,multicenter,large sample randomized controlled trials.