Efficacy Of Robot-assisted Lobectomy For NSCLC And Risk Factors For Lymph Node Metastasis In T1 NSCLC

ObjectiveTo investigate the perioperative efficacy and long-term survival of RAL in treating NSCLC,and compare RAL with VAL.To explore the risk factors for lymph node metastasis in patients with pathologic T1 stage NSCLC.MethodsIn the first part of the study,146 patients underwent RAL or VAL were retrospectively included.After matching the baseline data of the patients with PSM,we observed the perioperative efficacy.Based on this,a prospective RCT to compare the efficacy of RAL with VAL to treat NSCLC was carried out since June 2017.The main endpoint was 30-day postoperative complication rate,secondary endpoints included long-term survival,lymph node resection,intraoperative blood loss,chest tube drainage,hospitalization costs,etc.As of August 2019,a total of 270 patients have been enrolled,including 134 in RAL group and136 in VAL group.In the second part of the study,1002 patients with pathologic stage T1 NSCLC were included.They were divided into two groups based on whether lymph node metastasis occurred,and their clinical and pathologic characteristics were collected.Multivariate logistic regression analysis was performed on indicators with significant differences to distinguish independent risk factors.ResultsIn the first part,a total of 136 patients in the retrospective study were successfully matched after PSM,77 in RAL group and 59 in VAL group.Compared with VAL,RAL dissected significantly more lobar(No.12)lymph nodes(0.63 vs.0.05,p < 0.001),but its cost was more expensive(75,978.65 vs.45,357.57 RMB,p <0.001).In the RCT,the 30-day postoperative complication rate after RAL was not worse than VAL(11.2% vs.14.7%,p =0.390).RAL had a better control of intraoperative bleeding(141.89 vs.156.92 ml,p = 0.035),and resected more lymph nodes(10.94 vs.8.90,p <0.001)and lymph node stations(5.37 vs.4.28,p < 0.001)than VAL.However,the total drainage volume(1041.19 vs.926.85 ml,p = 0.028)and hospitalization costs(84909.42 vs.53659.52 RMB,p < 0.001)of RAL were higher than VAL.In the second part,all patients with pathological lymph node metastasis had a performace of solid tumor on their preoperative imaging.The multivariate regression analysis showed that clinical N1(OR = 6.671,95% CI: 1.719-25.893)or N2(OR = 2.708,95% CI: 1.364-5.379)stage and preoperative blood CEA levels exceeding 5 ng / m L(OR =2.407,95% CI: 1.263-4.589)were risk factors for lymph node metastasis in patients with pathologic T1 NSCLC.ConclusionsBased on the retrospective PSM research and the prospective RCT,RAL was safe and effective in treating NSCLC and its perioperative efficacy was similar to VAL.RAL was superior in lymph node dissection and control of intraoperative bleeding,but the cost was relatively expensive.The long-term survival results of RAL require further follow up.Performace of solid tumor on preoperative imaging,clinical N1 or N2 stage and preoperative blood CEA levels exceeding 5 ng / m L were risk factors for lymph node metastasis in p T1 NSCLC patients.