title: A systematic review and meta-analysis of portal vein ligation versus portal vein embolization for elective liver resection.
abstract: BACKGROUND
  This meta-analysis aimed to review the percentage increase in future liver remnant (FLR) and perioperative outcomes after portal vein ligation (PVL) and portal vein embolization (PVE) before liver resection.
  
  
  METHODS
  An electronic search was performed of the MEDLINE, EMBASE, and PubMed databases using both subject headings (MeSH) and truncated word searches to identify all articles published that related to this topic. Pooled risk ratios were calculated for categorical outcomes and mean differences for secondary continuous outcomes using the fixed-effects and random-effects models for meta-analysis.
  
  
  RESULTS
  Seven studies involving 218 patients met the inclusion criteria. There was no difference in the increase in FLR between the 2 groups 39% (PVE) versus 27% (PVL; mean difference [MD] 6.04; 95% CI, -0.23, 12.32; Z = 1.89; P = .06). Similarly, there was no difference in the morbidity (risk ratio [RR], 1.08; 95% CI, 0.55, 2.09; Z = 0.21; P = .83) and mortality (RR, 0.87; 95% CI, 0.19, 3.92; Z = 0.18; P = .85) in the 2 groups after liver resection. While awaiting liver resection after PVL and PVE, no difference was noted in the number of patients developing disease progression (RR, 0.93; 95% CI, 0.52, 1.66; Z = 0.24; P = .81). In a subset analysis comparing FLR with PVE and PVL as part of the procedure called an associating liver partition with PVL for staged hepatectomy (ALPPS), there was a significant increase in FLR in favor of ALPPS (MD, -17.09; 95% CI, -32.78, -1.40; Z = 2.14; P = .03).
  
  
  CONCLUSIONS
  PVL and PVE result in comparable percentage increase in FLR with similar morbidity and mortality rates. The ALPPS procedure results in an improved percentage increase in FLR compared with PVE alone.
authors.affiliation: St James Hospital, Leeds, West Yorkshire, United Kingdom. Electronic address: sanjay.pandanaboyana@gmail.com.
authors.forename: Sanjay
authors.initials: S
authors.lastname: Pandanaboyana
authors.affiliation: St James Hospital, Leeds, West Yorkshire, United Kingdom.
authors.forename: Richard
authors.initials: R
authors.lastname: Bell
authors.affiliation: St James Hospital, Leeds, West Yorkshire, United Kingdom.
authors.forename: Ernest
authors.initials: E
authors.lastname: Hidalgo
authors.affiliation: St James Hospital, Leeds, West Yorkshire, United Kingdom.
authors.forename: Giles
authors.initials: G
authors.lastname: Toogood
authors.affiliation: St James Hospital, Leeds, West Yorkshire, United Kingdom.
authors.forename: K Raj
authors.initials: KR
authors.lastname: Prasad
authors.affiliation: Department of Surgery, Auckland City Hospital, Auckland, New Zealand.
authors.forename: Adam
authors.initials: A
authors.lastname: Bartlett
authors.affiliation: St James Hospital, Leeds, West Yorkshire, United Kingdom.
authors.forename: J Peter
authors.initials: JP
authors.lastname: Lodge
mesh_terms: D018450:Disease Progression; D017558:Elective Surgical Procedures / Q000379:methods*; D004621:Embolization, Therapeutic; D006498:Hepatectomy / Q000379:methods* / Q000401:mortality; D006801:Humans; D006984:Hypertrophy; D008026:Ligation; D008099:Liver / Q000254:growth & development* / Q000473:pathology / Q000601:surgery; D008113:Liver Neoplasms / Q000601:surgery*; D015233:Models, Statistical; D011169:Portal Vein / Q000601:surgery*; D011183:Postoperative Complications / Q000453:epidemiology; D016896:Treatment Outcome