Propensity score-based analysis of outcomes of laparoscopic versus open liver resection for colorectal metastases

BackgroundThere is a need for high-level evidence regarding the added value of laparoscopic (LLR) compared with open (OLR) liver resection. The aim of this study was to compare the surgical and oncological outcomes of patients with colorectal liver metastases (CRLM) undergoing LLR and OLR using propensity score matching to minimize bias. MethodsThis was a single-centre retrospective study using a prospective database of patients undergoing liver resection for CRLM between August 2004 and April 2015. Co-variates selected for matching included: number and size of lesions, tumour location, extent and number of resections, phase of surgical experience, location and lymph node status of primary tumour, perioperative chemotherapy, unilobar or bilobar disease, synchronous or metachronous disease. Prematching and postmatching analyses were compared. Surgical and oncological outcomes were analysed. ResultsSome 176 patients undergoing LLR and 191 having OLR were enrolled. After matching, 133 patients from each group were compared. At prematching analysis, patients in the LLR group showed a longer overall survival (OS) and higher R0 rate than those in the OLR group (P=0047 and P=0030 respectively). Postmatching analyses failed to confirm these results, showing similar OS and R0 rate between the LLR and OLR group (median OS: 552 versus 653months respectively, hazard ratio 070 (95 per cent c.i. 042 to 105; P=0082); R0 rate: 925 versus 865 per cent, P=0186). The 5-year OS rate was 625 (95 per cent c.i. 455 to 715) per cent) for OLR and 643 (482 to 695) per cent for LLR. Longer duration of surgery, lower blood loss and morbidity, and shorter postoperative stay were found for LLR on postmatching analysis. ConclusionPropensity score matching showed that LLR for CRLM may provide R0 resection rates and long-term OS comparable to those for OLR, with lower blood loss and morbidity, and shorter postoperative hospital stay. Good results for laparoscopic liver resections