title: Trends in centralization of cancer surgery.
abstract: BACKGROUND
  The association between procedure volume and clinical outcomes has led many to advocate centralization of cancer procedures at high-volume centers (HVCs). Regional studies show practice patterns changing with increasing centralization of esophageal and pancreatic procedures at HVCs but little change for colorectal procedures. We hypothesize that similar trends are occurring nationwide.
  
  
  METHODS
  Secondary data analysis was performed by means of the National Inpatient Sample. We examined trends in hospital procedure volume from 1999 to 2007 for all extirpative esophageal, pancreatic, and colorectal cancer procedures. Survey-weighted multivariate logistic regressions were used to examine the likelihood of surgery at a low-volume center (LVC) over time as well as to determine sociodemographic factors associated with surgery at LVCs.
  
  
  RESULTS
  A total of 351,164 cases met the inclusion criteria (6,345 esophagus, 17,658 pancreas, 255,753 colon, 71,408 rectum). The likelihood of surgery at a LVC in 2007 compared to 1999 was as follows: esophagus odds ratio [OR] 0.42 (95% confidence interval [95% CI], 0.34, 0.53), pancreas OR 0.40 (95% CI, 0.35, 0.46), colon OR 0.88 (95% CI, 0.85, 0.91), rectum OR 0.83 (95% CI, 0.78, 0.89). Admission through an emergency department was associated with a higher likelihood of surgery at a LVC, even after adjusting for clinical and sociodemographic factors. Volume was also associated with race and payer; black patients and the uninsured were particularly likely to remain at LVCs.
  
  
  CONCLUSIONS
  Practice patterns have changed substantially to follow national recommendations for centralization of complex cancer surgery. Despite this, disparities remain with regard to access to HVCs.
authors.affiliation: Department of Surgery, University of North Carolina, Chapel Hill, NC, USA. karyn_stitzenberg@med.unc.edu
authors.forename: Karyn B
authors.initials: KB
authors.lastname: Stitzenberg
authors.forename: Neal J
authors.initials: NJ
authors.lastname: Meropol
mesh_terms: D000328:Adult; D004067:Digestive System Neoplasms / Q000601:surgery*; D005260:Female; D054625:Healthcare Disparities; D006761:Hospitals / Q000706:statistics & numerical data* / Q000639:trends*; D006801:Humans; D008297:Male; D012189:Retrospective Studies; D014481:United States