Minimally invasive liver surgery for perihilar and intrahepatic cholangiocarcinoma: systematic review and meta-analysis of comparative studies

Background: The implementation of minimally invasive liver surgery (MILS) for perihilar (PHC) and intrahepatic cholangiocarcinoma (IHC) remains limited and a systematic review including only comparative studies of MILS versus the open approach is lacking. This systematic review and meta-analysis aimed to assess the safety and efficacy of minimally invasive surgery in patients with hilar and intrahepatic cholangiocarcinomas. Methods: Systematic review in the PubMed, Embase, and Cochrane databases for original studies comparing at least five patients undergoing MILS with open liver surgery for PHC and IHC. Meta-analysis included the primary outcomes of morbidity and mortality. Secondary outcomes included post-operative outcomes, recurrence, disease-free survival, and resection margins. Results: Overall, 37 comparative non-randomised studies with 4863 patients were included, of which 24% PHC and 76% IHC. In 21 studies, propensity score matching was performed. In total, 2106 laparoscopic, 75 robotic, and 2662 open procedures were analysed. The conversion rate was median 11.5% [IQR 10.0–12.5]. MILS probably resulted in reduced rates of major morbidity, 13.3% vs 18.8% (OR 0.75, 95%CI 0.62–0.90), mortality, 3.0% vs 4.5% (OR 0.69, 95%CI 0.49–0.97), and shorter hospital stay, 8.0 vs 10.9 days (MD -2.1, 95%CI -2.8 – -1.5). MILS resulted in higher rate of R0 resections in PSM cohort, 90.4% vs 81.4%, (OR 1.40, 95%CI 1.13–1.74) and better 3-year disease-free survival rate (49.9% vs 38.5%, HR3-year 3.2, 95%CI 3.1–3.3). In the subgroup of 1180 patients in whom a hepatico-jejunostomy was performed (498 laparoscopic, 65 robotic, 617 open) MILS remained associated with reduced major morbidity, 20.9% vs 27.6% (OR 0.88, 95%CI 0.64–1.21) and resulted in better mortality, 4.2% vs 4.9% (OR 0.51, 95%CI 0.30–0.86), as compared to the open approach. Overall, the rate of biliary leakage was likely similar, 10.6% versus 11.7% (OR 0.83, 95%CI 0.52–0.77). Conclusion: This systematic review of non-randomised comparative studies suggests that MILS for PHC and IHC may result in a similar safety profile with benefits in patient recovery and oncological outcomes as compared to OLS. Prospective comparative studies, especially including robotic MILS, are warranted.