Impact of laparoscopic parenchyma-sparing resection of posterosuperior segments of the liver on surgical outcomes: a multicenter study based on propensity score analysis

Background: We compared the surgical outcomes after parenchyma-sparing resection of the posterosuperior segment (PSS) between the patients undergoing laparoscopic liver resection (LLR) and open liver resection (OLR).
Methods: The subjects were 617 patients who underwent liver resection for the hepatic lesions in PSS at eight centers. We conducted propensity score matching (PSM) analysis and inverse probability weighting method (IPW).  
Results: In the unmatched cohort, several confounding variables regarding type of liver resection (segmentectomy or limited resection), lesion size, superficial location, and proximity to the major hepatic vessels were unbalanced between the two groups. After PSM and IPW adjustment, the two groups were well-balanced on all variables. LLR reduced intra-operative blood loss and the incidence rate of postoperative complication compared with OLR in both PSM and IPW cohorts. The odds ratios of LLR for postoperative complication in PSM and IPW cohorts were 0.38 and 0.40 (P<0.001 and P<0.001, respectively). Of postoperative complications, pulmonary complication were less likely to be dobserved in the LLR group than the OLR group in PSM and IPW cohort.
Conclusions: For parenchyma-sparing liver resection of hepatic lesions in the PSS, LLR showed the clinical benefits including reduced intra-operative blood loss and lower postoperative complication rate compared with OLR.