Comparison of Robotic and Laparoscopic Liver Resection Within One Couinaud Segment: A Propensity Score-Based Analysis

Minimally invasive liver resection (MILR), including laparoscopic (LLR) and robot-assisted (RLR) approaches, is being increasingly utilized for hepatic tumors, though comparative evidence for hepatectomy within one liver segment remains limited.

From January 2015 to December 2024, 2290 patients underwent MILR for hepatic tumors at our institution. After excluding combined resections (other than cholecystectomy), resections involving more than one Couinaud segment, multiple tumors in different segments, and incomplete data, 718 single-segment cases (LLR, n = 630; RLR, n = 88) were analyzed. Propensity score matching (PSM) at 1:1 and 1:3 ratios was performed to balance baseline covariates.

Before matching, RLR had longer operative time (226.5 vs. 197.0 min; p = 0.027) and greater blood loss (150 vs. 100 mL; p = 0.037) than LLR, but less frequent Pringle maneuver use (53.4% vs. 64.8%; p = 0.038). After 1:1 and 1:3 propensity score matching, operative time, blood loss, conversion, transfusion, and R0 resection were comparable, whereas Pringle use remained lower with RLR (51.2% vs. 66.7%, p = 0.041; 51.2% vs. 64.3%, p = 0.035). Postoperatively, length of stay was longer after RLR in the unmatched cohort (8.0 vs. 7.0 days; p = 0.006), but not after matching (both 7.0 days). Major complications, including post-hepatectomy liver failure, hemorrhage, and bile leakage, were similar; no perioperative deaths occurred. Subgroup analyses showed shorter length of stay with RLR in advanced IWATE cases (RR, 0.79; 95% CI, 0.64-0.97; p = 0.022) and caudate resections (RR, 0.65; 95% CI, 0.46-0.90; p = 0.010), and shorter operative time in advanced IWATE cases (RR, 0.85; 95% CI, 0.74-0.99; p = 0.039), with significant interaction across IWATE levels (p = 0.047).

RLR and LLR yielded comparable perioperative outcomes in single-segment liver resections. Nonetheless, RLR was associated with reduced reliance on vascular inflow occlusion and conferred selective advantages in anatomically complex or high-difficulty cases.