Machine Perfusion and Oncologic Outcomes After Liver Transplantation for Hepatocellular Carcinoma: A Systematic Review and Meta-Analysis

Background: Machine perfusion has emerged as a promising strategy to attenuate ischemia–reperfusion injury during liver transplantation (LT). However, its impact on hepatocellular carcinoma (HCC) recurrence and post-transplant oncologic outcomes remains uncertain. We performed a systematic review and meta-analysis evaluating the association between machine perfusion and oncologic outcomes after LT for HCC. Methods: A systematic literature search of PubMed/MEDLINE, Embase, and Web of Science was conducted from database inception to May 2026. Comparative clinical studies evaluating machine perfusion and oncologic outcomes after LT for HCC were included. The primary outcome was recurrence-free survival (RFS). Secondary outcomes included HCC recurrence, early recurrence, overall survival (OS), and graft-related outcomes. Risk of bias was assessed using the ROBINS-I tool. Random-effects meta-analyses were performed when appropriate. Results: Six comparative clinical studies involving HCC recipients undergoing LT were included. All studies were observational, and no randomized controlled trial was identified. Three studies were judged to have a moderate risk of bias and three were judged to have a serious risk of bias. In the primary RFS meta-analysis, machine perfusion was associated with a numerically lower risk of recurrence or death, although the pooled estimate did not reach statistical significance (HR 0.34, 95% CI 0.07–1.77; p = 0.20). The binary recurrence analysis also demonstrated a numerically lower risk of HCC recurrence after machine perfusion (RR 0.40, 95% CI 0.13–1.20; p = 0.10). Several studies reported favorable associations between machine perfusion and early recurrence, while large adjusted cohorts reported associations with improved RFS and OS. Machine perfusion was generally associated with lower markers of ischemia–reperfusion injury, including postoperative aminotransferase release. Conclusions: Current evidence suggests a potential favorable association between machine perfusion and oncologic outcomes after LT for HCC. However, the pooled estimates from the primary analyses were not statistically significant, and the evidence remains limited by the small number of studies, observational designs, heterogeneity, and potential cohort overlap. Further prospective studies are required before an oncologic benefit of machine perfusion can be established.