Short-term And Long-term Outcomes Of Robotic-assisted Versus Video-assisted Lobectomy For Early-stage Non-small Cell Lung Cancer:a Propensity Score-matched Study

Object:The purpose of this study was to compare the short-term and long-term outcome of robotic and thoracoscopic assisted lobectomy for early stage NSCLC(Non-Small Cell Lung Cancer)to explore the clinical value of robot-assisted lobectomy in the treatment of early stage NSCLC.Methods:The clinical data of patients with pathological stage I or stage II NSCLC who underwent robot-assisted or video-assisted lobectomy in our hospital from January 2012 to June 2017 were retrospectively analyzed.A total of 399 patients met the exclusion criteria.According to the surgical procedure,it was divided into RAL(Robot-Assisted Lobectomy)group(151 cases)and VAL(Video-Assisted Lobectomy)group(248 cases).The distribution of the largest diameter,lesion location,differentiation degree and pathological type of the two groups was not balanced,and the difference was statistically significant(P<0.05).Using the PSM(propensity score matching)method,145 cases of the RAL group and the VAL group were selected according to the 1:1 nearest neighbor matching.The data of the blood loss during the operation,the chest drainage volume on the first day after surgery,the chest drainage volume on the second day after surgery,the postoperative tube time,the postoperative hospital stay,total number of dissected lymph nodes and number of dissected lymph node station of the patients were collected.Telephone or outpatient follow-up was performed to calculate overall survival and disease-free survival.Statistical analysis was performed using SPSS24.0 software.Continuous variables were expressed as mean±standard deviation,and t-test was used for comparison between groups.Outlier categorical variables were compared by chi-square test for comparison between groups;The Mann-Whitney was used to compare the ordered data;the overall survival rate and disease-free survival rate were compared between groups by Kaplan-Meier method and Log-rank test.The difference was statistically significant at P<0.05.Result:Finally,290 patients with early stage NSCLC were included in the analysis.There were 163 male patients and 127 female patients with an average age of 61.4 years.The maximum diameter of the tumor was 2.7 cm,and moderate differentiation is the main type,accounting for 46%.Adenocarcinoma is the main type,accounting for 74%,TNM staging is mainly IA,accounting for 64.1%,IB is 18.3%,IIA is 13.1%,and IIB is 4.5%.There were no significant differences in gender,age,smoking history,tumor maximum diameter,lesion location,differentiation degree,pathological type and TNM staging between the two groups(P>0.05).Compared with the VAL group,the RAL group had less blood loss during operation(53±40 ml vs 216±167 ml,P=0.000)and less postoperative drainage(postoperative day 1:246± 124 ml vs.336±198 ml,P=0.000;2 days after surgery:280± 131ml vs 310± 133ml,P=0.053),more lymph node dissection group(5 groups vs 4 groups,P=0.000)and more lymph node dissection(18 pieces vs 12 pieces,P=0.000).There was no significant difference in postoperative tube time and postoperative hospital stay between the two groups(P>0.05).In terms of long-term prognosis,the 3-year survival rate of the RAL group and the VAL group was 86.2%vs 83.7%,respectively,and the 5-year survival rate was 79.2%vs.70.5%.The 3-year disease-free survival rate of the RAL group and the VAL group was 79.3%to 72.8%,and the 5-year disease-free survival rate was 75.5%to 60.1%.The overall survival rate and disease-free survival rate of the RAL group were better,but the difference was not statistically significant(P>0.05).According to the pathological staged analysis,the 5-year survival rate of the I stage RAL group and the VAL group was 85.4%vs 74.6%,respectively,and the 5-year disease-free survival rate was 83.2%vs 63.1%.The 5-year survival rate of the II stage RAL group and the VAL group was 57.6%vs 49.2%,respectively,and the 5-year disease-free survival rate was 46.6%vs 42.5%.The overall survival rate and disease-free survival rate of the RAL group in stage I and II were slightly better than those in the VAL group,but the difference was not statistically significant(P>0.05).Conclusion:In the treatment of early stage NSCLC,RAL and VAL have comparable long-term survival and disease-free survival.Robotic surgery seems to have a more thorough lymph node dissection and better assessment of lymph node status.