Propensity score-matched analysis comparing robotic versus laparoscopic minor liver resections of the anterolateral segments: an international multi-center study of 10,517 cases

Objective: To compare the outcomes of robotic minor liver resections (RMLR) versus laparoscopic (L) MLR of the anterolateral segments. Background: Robotic liver surgery has been gaining prominence over the years with increasing usage for a myriad of hepatic resections. Robotic liver resections(RLR) has demonstrated non-inferiority to laparoscopic(L)LR while illustrating advantages over conventional laparoscopy especially for technically difficult and major LR. However, the advantage of RMLR for the anterolateral(AL) (segments II, III, IVb, V and VI) segments, has not been clearly demonstrated. Methods: Between 2008 to 2022, 15,356 of 29,861 patients from 68 international centres underwent robotic(R) or laparoscopic minor liver resections (LMLR) for the AL segments Propensity score matching (PSM) analysis was performed for matched analysis. Results: 10,517 patients met the study criteria of which 1,481 underwent RMLR and 9,036 underwent LMLR. A PSM cohort of 1,401 patients in each group were identified for analysis. Compared to the LMLR cohort, the RMLR cohort demonstrated significantly lower median blood loss (75ml vs. 100ml, p<0.001), decreased blood transfusion (3.1% vs. 5.4%, p=0.003), lower incidence of major morbidity (2.5% vs. 4.6%, p=0.004), lower proportion of open conversion (1.2% vs. 4.5%, p<0.001), shorter post operative stay (4 days vs. 5 days, p<0.001), but higher rate of 30-day readmission (3.5% vs. 2.1%, p=0.042). These results were then validated by a 1:2 PSM analysis. In the subset analysis for 3,614 patients with cirrhosis, RMLR showed lower median blood loss, decreased blood transfusion, lower open conversion and shorter post operative stay than LMLR. Conclusion: RMLR demonstrated statistically significant advantages over LMLR even for resections in the AL segments although most of the observed clinical differences were minimal.