Portal vein ligation versus portal vein embolization for induction of hypertrophy of the future liver remnant: A systematic review and meta-analysis

An important risk of major hepatic resection is postoperative liver failure, which is directly related to insufficient future liver remnant (FLR). Portal vein embolization (PVE) and portal vein ligation (PVL) can minimize this risk by inducing hypertrophy of the FLR. The aim of this systematic review and meta-analysis was to compare the efficacy and safety of PVE and PVL for FLR hypertrophy. A systematic search was conducted on the17^th of January 2017. The methodological quality of the studies was assessed using the Oxford Critical Appraisal Skills Program for cohort studies. The primary endpoint was the relative rate of hypertrophy of the FLR. Number of cancelled hepatic resection and postoperative morbidity and mortality were secondary endpoints. For meta-analysis, the pooled hypertrophy rate was calculated for each intervention. The literature search identified 21 eligible studies with 1953 PVE and 123 PVL patients. All studies were included in the meta-analysis. No significant differences were found regarding the rate of FLR hypertrophy (PVE 43.2%, PVL 38.5%, p = 0.39). The number of cancelled hepatic resections due to inadequate hypertrophy was significantly lower after PVL (p = 0.002). No differences were found in post-intervention mortality and morbidity. This meta-analysis demonstrated no significant differences in safety and rate of FLR hypertrophy between PVE and PVL. PVE should be considered as the preferred strategy, since it is a minimally invasive procedure. However, during a two-stage procedure, PVL can be performed with expected comparable outcome as PVE.