title: Meta-analysis of clinical outcome after first and second liver resection for colorectal metastases.
abstract: BACKGROUND
  The perioperative risk and long-term survival benefit of repeat hepatectomy for patients with liver metastases from colorectal cancer, compared with that of a first liver resection, has been reported with varying results in the literature.
  
  
  METHODS
  The literature was searched using Medline, Embase, Ovid, and Cochrane databases for all studies published from 1992 to 2006. Two authors independently extracted data using the following outcomes: postoperative complications and mortality; disease recurrence; and long-term survival. Trials were assessed using the modified Newcastle-Ottawa Score. Random-effect meta-analytical techniques were used for analysis.
  
  
  RESULTS
  Twenty-one studies met the inclusion criteria, comprising 3,741 patients. The use of adjuvant chemotherapy was similar in both groups (odds ratio [OR] = 0.97; 95% confidence interval [CI] = 0.54, 1.74; P = .92), as was the number of hepatic nodules present at the time of first or second resection (weighted mean difference [WMD] = 0.18; 95% CI = -0.22, 0.57; P = .380). Wedge resection was carried out less often at first hepatectomy (39% vs 46%; OR = 0.66; 95% CI = 0.44, 1.00; P = .05). There was significantly less blood loss in patients undergoing first versus second hepatectomy (WMD = 238 ml; 95% CI = 90, 385; P = .002). There was no difference in perioperative morbidity (OR = 1.01; 95% CI = 0.65, 1.55; P = .98), mortality (OR = 1.01; 95% CI = 0.18, 5.72; P = .99) or long-term survival (HR = 0.90; 95% CI = .66, 1.24; P = .530) between groups.
  
  
  CONCLUSIONS
  Repeat hepatectomy for patients with colorectal cancer metastases is safe and provides survival benefit equal to that of a first liver resection.
authors.affiliation: Imperial College London, Department of Biosurgery and Surgical Technology, St. Mary's Hospital, London, UK.
authors.forename: Anthony
authors.initials: A
authors.lastname: Antoniou
authors.forename: Richard E
authors.initials: RE
authors.lastname: Lovegrove
authors.forename: Henry S
authors.initials: HS
authors.lastname: Tilney
authors.forename: Alexander G
authors.initials: AG
authors.lastname: Heriot
authors.forename: Timothy G
authors.initials: TG
authors.lastname: John
authors.forename: Myrddin
authors.initials: M
authors.lastname: Rees
authors.forename: Paris P
authors.initials: PP
authors.lastname: Tekkis
authors.forename: Fenella K S
authors.initials: FK
authors.lastname: Welsh
mesh_terms: D015179:Colorectal Neoplasms / Q000401:mortality; D006498:Hepatectomy / Q000009:adverse effects; D006801:Humans; D008113:Liver Neoplasms / Q000401:mortality / Q000556:secondary* / Q000601:surgery*; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000601:surgery; D012086:Reoperation; D012307:Risk Factors; D012449:Safety; D015996:Survival Rate; D016896:Treatment Outcome