title: Increased risk of hepatocellular carcinoma after cholecystectomy.
abstract: BACKGROUND
  The association between gall bladder removal (cholecystectomy) and hepatocellular carcinoma warrants investigation. An increased intrahepatic bile duct pressure following cholecystectomy might cause chronic inflammation in the surrounding liver tissue, which might induce cancer development.
  
  
  METHODS
  A nationwide Swedish population-based cohort study in 1965-2008 included 345,251 patients undergoing cholecystectomy because of gallstone. The number of observed hepatocellular carcinoma cases was divided by the expected number, calculated from the corresponding background Swedish population, thus providing standardised incidence ratios (SIRs) with 95% confidence intervals (CIs).
  
  
  RESULTS
  During follow-up of 4,854,969 person-years, 333 new cases of hepatocellular carcinoma were identified, rendering an overall increased risk (SIR 1.24, 95% CI: 1.11-1.38). The risk increased with longer follow-up (P for trend=0.003). Among patients who underwent cholecystectomy 30-43 years earlier, SIR was 2.00 (95% CI: 1.32-2.87). The results were similar after exclusion of 15,634 patients with any recorded risk factor, that is, diabetes, obesity, hepatitis, liver cirrhosis, alcoholism, or blood transfusion.
  
  
  CONCLUSIONS
  Cholecystectomy might be associated with a long-term increased risk of hepatocellular carcinoma.
authors: Upper Gastrointestinal Research, Department of Molecular Medicine and Surgery, Karolinska Institutet, Norra Stationsgatan 67, Level 2, 171 76 Stockholm, Sweden. Jesper.Lagergren@ki.se
authors: J
authors: J
authors: Lagergren
authors: F
authors: F
authors: Mattsson
authors: H
authors: H
authors: El-Serag
authors: H
authors: H
authors: Nordenstedt
references: Eur J Epidemiol. 2009;24(11):659-67
references: 19504049
references: IARC Sci Publ. 1987;(82):1-406
references: 3329634
references: Acta Oncol. 2009;48(1):27-33
references: 18767000
references: Int J Cancer. 2001 Oct 15;94(2):290-6
references: 11668511
references: Gastroenterology. 2001 Sep;121(3):548-53
references: 11522738
references: Br J Cancer. 1999 Feb;79(3-4):640-4
references: 10027343
references: Gastroenterology. 2007 Jun;132(7):2557-76
references: 17570226
references: Br J Cancer. 2005 Apr 11;92(7):1307-9
references: 15770220
references: Gastroenterology. 1984 Nov;87(5):1154-9
references: 6479537