Propensity-score Matched and Coarsened-exact Matched Analysis Comparing Robotic and Laparoscopic Major Hepatectomies: An International Multicenter Study of 4822 Cases

Objective: To compare the outcomes between robotic major hepatectomy (R-MH) and laparoscopic major hepatectomy(L-MH). Background: Robotic techniques may overcome the limitations of laparoscopic liver resection. However, it is unknown whether robotic major hepatectomy (R-MH) is superior to laparoscopic major hepatectomy (L-MH). Methods: This is a post hoc analysis of a multicenter database of patients undergoing R-MH or L-MH at 59 international centers from 2008 to 2021. Data on patient demographics, center experience/ volume, perioperative outcomes and tumor characteristics were collected and analyzed. 1:1 propensity score matched (PSM) and coarsened-exact matched (CEM) analysis was performed to minimize selection bias between both groups. Results: A total of 4822 cases met the study criteria, of which 892 underwent R-MH and 3930 underwent L-MH. Both 1:1 PSM, (841 R-MH vs. 841 L-MH) and CEM (237 R-MH vs. 356 L-MH) were performed. R-MH was associated with significantly less blood loss (PSM:200.0 [IQR:100.0, 450.0] ml vs. 300.0 [IQR:150.0, 500.0] ml; P=0.012; CEM:170.0 [IQR: 90.0, 400.0] ml vs. 200.0 [IQR:100.0, 400.0] ml; P=0.006), lower rates of Pringle maneuver application (PSM: 47.1% vs. 63.0%; P<0.001; CEM: 54.0% vs 65.0%; P=0.007) and open conversion (PSM: 5.1% vs. 11.9%; P<0.001; CEM: 5.5% vs. 10.4%, P=0.04) compared to L-MH. On subset analysis of 1273 cirrhotic patients, R-MH was associated with a lower postoperative morbidity rate (PSM: 19.5% vs. 29.9%; P=0.02; CEM 10.4% vs. 25.5%; P=0.02) and shorter postoperative stay (PSM: 6.9 [IQR: 5.0, 9.0] days vs. 8.0 [IQR: 6.0 11.3] days; P<0.001; CEM 7.0 [IQR: 5.0, 9.0] days vs. 7.0 [IQR: 6.0, 10.0] days; P=0.047). Conclusion: This international multicenter study demonstrated that R-MH was comparable to L-MH in safety and was associated with reduced blood loss, lower rates of Pringle maneuver application and conversion to open surgery

Propensity Score-Matching Analysis Comparing Robotic Versus Laparoscopic Limited Liver Resections of the Posterosuperior Segments: An International Multi-Center Study

Objective: To compare the outcomes of robotic limited liver resections (RLLR) versus laparoscopic limited liver resections (LLLR) of the posterosuperior segments. Background: Both laparoscopic and robotic liver resections have been used for tumors in the posterosuperior liver segments. However, the comparative performance and safety of both approaches have not been well examined in existing literature. Methods: This is a post hoc analysis of a multicenter database of 5,446 patients who underwent RLLR or LLLR of the posterosuperior segments (I, IVa, VII and VIII) at 60 international centers between 2008 and 2021. Data on baseline demographics, center experience and volume, tumour features and perioperative characteristics were collected and analysed. Propensity score matching (PSM) analysis (in both 1:1 and 1:2 ratios) was performed to minimize selection bias. Results: A total of 3510 cases met the study criteria, of whom 3049 underwent LLLR (87%) and 461 underwent RLLR (13%). After PSM (1:1: and 1:2), RLLR was associated with a lower open conversion rate (10 of 449 [2.2%] vs. 54 of 898 [6.0%]; P=0.002), less blood loss (100 mL [IQR; 50-200] days vs. 150 mL [IQR; 50-350]; P<0.001) and a shorter operative time (188 min [IQR; 140-270] vs. 222 min [IQR; 158-300]; P<0.001). These improved perioperative outcomes associated with RLLR were similarly seen in a subset analysis of patients with cirrhosis - lower open conversion rate (1 of 136 [0.7%] vs. 17 of 272 [6.2%]; P=0.009), less blood loss (100 mL [IQR; 48-200] vs. 160 mL [IQR; 50-400]; P<0.001) and shorter operative time (190 min [IQR; 141-258] vs. 230 min [IQR; 160-312]; P=0.003). Post-operative outcomes in terms of readmission, morbidity and mortality were similar between RLLR and LLLR in both the overall PSM cohort and cirrhosis patient subset. Conclusion: RLLR for the posterosuperior segments was associated with superior perioperative outcomes in terms of decreased operative time, blood loss and open conversion rate when compared to LLLR