A Propensity Score-Matching Analysis Of Robotic VS Open Pancreaticoduodenectomy On Oncological Outcomes For Ductal Adenocarcinoma

Objective:This study focused on the comparison of oncological outcomes between robot-assisted pancreaticoduodenectomy（RPD）and open pancreaticoduodenectomy（OPD）terming pancreatic ductal adenocarcinoma（PDAC）.Background:Along with the great spread and advance of the robot-assisted approach in pancreatic surgery,the surgeons began wondering if there existed the oncological outcome differences of RPD comparing to OPD in PDAC patients.Methods:Information from 672 PDAC patients undergoing OPD or RPD between January 2013and December 2017 at a single institution was reviewed.Propensity score nearest-neighbor 1:1matching was performed between patients undergoing RPD or OPD based on relevant confounding variables.The primary outcomes were oncological and survival and the second outcomes focused on perioperative outcomes.Results:Of 672 eligible patients,115（17.1%）underwent RPD.After propensity score-matching,115 pairs patients were enrolled into the post-matching database.Controlling confounders,no significant difference of the median overall survival（27 month vs 20 month,P=0.119,OR=0.71）and the median disease-free survival（15 month vs 15 month,P=0.867,OR=1.03）was noticed between the RPD and OPD cohorts.There was no differences in evaluated lymph node[12（6-18）vs 11（6-16）,P=0.557]and R0 resection ratio（86%vs 90%,P=0.422）.Less N₂ stage（14%vs 4%,P=0.023）,less positive lymph nodes[0（0-1）vs 1（0-3）,P=0.007]and lower lymph node ratio[0（0-0.09）vs 0.05（0-0.18）,P=0.045]were observed in RPD cohort compared with OPD cohort.After adjustment,the differences of the overall survival（P=0.272,OR=0.79）and the DFS（P=0.673,OR=1.08）were still not significant statistically.Conclusion:Comparative survival was observed after OPD and RPD for PDAC.However the differences in positive lymph node retrieval strengthen the need for further prospective randomized controlled trials to confirm the oncological safety of PRD.