title: Large variation in the utilization of liver resections in stage IV colorectal cancer patients with metastases confined to the liver.
abstract: BACKGROUND
  Surgical resection of both the primary tumor and all metastases is considered the only chance of cure for patients with stage IV colorectal cancer. The aim of this study was to investigate change over time in the utilization of liver resections, as well as possible institutional variations.
  
  
  METHODS
  All patients diagnosed with stage IV colorectal cancer with metastases confined to the liver (n = 1617) between 2004 and 2012 were selected from the population-based Eindhoven Cancer Registry. The proportion of patients undergoing liver resection was investigated. Institutional variation in the period 2010-2012 was analyzed using logistic regression. Kaplan-Meier and Cox regression analyses were used to analyze overall survival.
  
  
  RESULTS
  The proportion of patients undergoing liver metastasectomy increased over time from 8% in 2004 to approximately 24% in 2012. There was a wide inter-hospital variation in the proportion of patients that underwent a liver resection (range: 14-34%) in the period 2010-2012. Liver resection was more often performed in younger patients and in rectal cancer patients. Median overall survival in patients undergoing liver resection was 55 months. Adjusted for potential confounders, resection of liver metastases was strongly associated with improved overall survival (HR 0.32, 95%CI 0.25-0.40).
  
  
  CONCLUSIONS
  This study shows that despite the excellent long-term prognosis for patients with stage IV colorectal cancer after liver resection, there is still a large institutional variation in the utilization of this potentially curative therapy.
authors.affiliation: Department of Surgery, Radboud University Medical Center, PO Box 9101, 6500 HB Nijmegen, The Netherlands. Electronic address: jorine.tlam-boer@radboudumc.nl.
authors.forename: J
authors.initials: J
authors.lastname: 't Lam-Boer
authors.affiliation: Department of Surgery, Amphia Hospital, PO Box 90157, 4800 RL Breda, The Netherlands. Electronic address: calali@amphia.nl.
authors.forename: C
authors.initials: C
authors.lastname: Al Ali
authors.affiliation: Netherlands Comprehensive Cancer Organisation, PO Box 90157, 4800 RL Breda, The Netherlands. Electronic address: r.verhoeven@ikz.nl.
authors.forename: R H A
authors.initials: RH
authors.lastname: Verhoeven
authors.affiliation: Department of Surgery, Maxima Medical Centre, Postbus 7777, 5500 MB Veldhoven, The Netherlands. Electronic address: r.roumen@mmc.nl.
authors.forename: R M H
authors.initials: RM
authors.lastname: Roumen
authors.affiliation: Netherlands Comprehensive Cancer Organisation, PO Box 90157, 4800 RL Breda, The Netherlands. Electronic address: v.lemmens@iknl.nl.
authors.forename: V E P P
authors.initials: VE
authors.lastname: Lemmens
authors.affiliation: Department of Surgery, Amphia Hospital, PO Box 90157, 4800 RL Breda, The Netherlands. Electronic address: arijken@amphia.nl.
authors.forename: A M
authors.initials: AM
authors.lastname: Rijken
authors.affiliation: Department of Surgery, Radboud University Medical Center, PO Box 9101, 6500 HB Nijmegen, The Netherlands. Electronic address: hans.dewilt@radboudumc.nl.
authors.forename: J H W
authors.initials: JH
authors.lastname: De Wilt
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D002277:Carcinoma / Q000556:secondary / Q000601:surgery*; D015179:Colorectal Neoplasms / Q000473:pathology*; D005260:Female; D006498:Hepatectomy / Q000706:statistics & numerical data*; D006801:Humans; D008113:Liver Neoplasms / Q000556:secondary / Q000601:surgery*; D008297:Male; D059146:Metastasectomy / Q000706:statistics & numerical data*; D008875:Middle Aged; D015999:Multivariate Analysis; D009426:Netherlands; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D016016:Proportional Hazards Models; D012004:Rectal Neoplasms / Q000473:pathology
keywords: Colorectal cancer; Liver resection; Metastasectomy; Metastases; Stage IV; Variation