The Propensity Score Matching Study Of Robot-assisted Thoracic Surgery And Video-assisted Thoracic Surgery For Mediastinal Lymph Node Dissection Of Non-small Cell Lung Cancer

Objective: Robot-assisted thoracic surgery(RATS)has not been fully evaluated for lymph node dissection(LND)in lung cancer surgery.The purpose of this study was to compare the LND outcomes and short-term and long-term prognosis of video-assisted thoracic surgery(VATS)and robot-assisted thoracic surgery(RATS).Method: We retrospectively analyzed the clinical data of 1608 patients who underwent lobectomy and mediastinal lymph node dissection in the Department of Thoracic Surgery,Affiliated Hospital of Qingdao University from January 2014 to December 2017.According to the different surgical methods,they were divided into RATS group(n =252)and VATS group(n = 1356).Through propensity score matched analysis(PSM),251 pairs of primary lung cancer patients were included in this study.LND-related outcomes were compared between the two groups,including LND-related complications(chylothorax,phrenic nerve palsy and bronchopleural fistula),perioperative parameters and long-term survival outcomes.SPSS 25.0 software was used for statistical analysis of relevant parameters.Bilateral P < 0.05 was considered statistically significant.Results: There was no significant difference in baseline data between RATS group and VATS group(P > 0.05).There was a significant difference in the median of total anatomical LN between the two groups(RATS : 18,VATS : 16;p = 0.001).Right upper area and hilum(# 2R + # 4R + # 10L)(RATS : 10,VATS : 7;p < 0.001),left lower paratracheal and hilar(# 4L + # 10L)(RATS : 4,VATS : 3;p = 0.024),aortic pulmonary area(# 5 + # 6)(RATS : 3,VATS : 3;p = 0.005)and interlobar and lobar(# 11 + # 12)LNs(RATS : 4,VATS : 3;p = 0.012).There was no significant difference in the incidence of total lymph node elevation(P = 0.228)and LND-related complications(P = 0.478)between the two groups.In addition,the operation time and total cost of hospitalization in the RATS group were higher than those in the VATS group,and the postoperative tube time was lower than that in the VATS group(P < 0.05).The recurrence-free survival(RFS)between the two groups was statistically significant(P <0.05).Conclusion: RATS can dissect LNs better than VATS,especially in bilateral superior mediastinal and hilar regions.Of course,this requires accumulating more cases and longer observation time to verify whether RATS can provide better LND quality.In terms of long-term survival,the RATS group was comparable to the VATS group in terms of 5-year overall survival(OS),and the 5-year recurrence-free survival(RFS)was superior to the VATS group.Although the operation time is relatively long and the total hospitalization cost is high,with the continuous improvement of medical technology and the decrease of consumables cost,the Da Vinci robotic surgical operation system is expected to play an increasingly important role in radical resection of lung cancer.