Robotic versus open hepatectomy for IWATE expert-level liver resection: a risk-adjusted comparative study.

BACKGROUND

Evidence directly comparing robotic and open hepatectomy for IWATE expert-level liver resection remains limited. This study aimed to compare perioperative outcomes between the two approaches in a high-volume hepatobiliary center.

METHODS

We reviewed 1706 consecutive patients who underwent hepatectomy for intrahepatic lesions between January 2024 and December 2025. Among them, 232 patients met the criteria for IWATE expert-level resection, including 70 robotic and 162 open cases. The primary outcome was major complications, defined as Clavien-Dindo grade ≥III. One-to-one propensity score matching was used as the primary risk-adjustment method. Overlap weighting was performed as a sensitivity analysis, with an additional malignancy-restricted analysis. Exploratory subgroup analyses were conducted for major complications and textbook outcome in liver surgery (TOLS).

RESULTS

Propensity score matching yielded 68 well-balanced pairs. In the matched cohort, robotic hepatectomy had longer operative time than open hepatectomy (median, 240.0 vs 205.5 min; P = 0.002), but lower estimated blood loss (100.0 vs 200.0 mL; P = 0.038) and shorter postoperative length of stay (6.0 vs 9.0 days; P < 0.001). Major complications were comparable between the robotic and open groups (13.2% vs 19.1%; P = 0.480). TOLS and severe liver-specific complications were also similar between groups. No significant between-group difference was observed in 90-day mortality. Findings from the overlap-weighted and malignancy-restricted analyses were directionally consistent with the primary analysis. In exploratory subgroup analyses, no significant interaction was observed across most prespecified subgroups, whereas a significant interaction with cirrhosis was detected for both major complications and TOLS.

CONCLUSIONS

Robotic hepatectomy was associated with reduced blood loss and shorter postoperative stay without increased major morbidity or mortality in selected patients undergoing IWATE expert-level liver resection at an experienced center. These findings support the selective application of robotic hepatectomy in technically demanding liver resections.