title: Cancer after cholecystectomy: record-linkage cohort study.
abstract: We investigated whether cholecystectomy is associated with subsequent cancer and, if so, whether the association is likely to be causal, by undertaking a retrospective cohort study using linked medical statistics, comprising a cholecystectomy group (n=39 254) and a reference cohort admitted for a range of other medical and surgical conditions (n=334 813). We found a short-term significant elevation of rates of cancers of the colon, pancreas, liver, and stomach after cholecystectomy, but no long-term elevation. Excluding colon cancers within 2 years of admission to hospital, the rate ratio for colon cancer after cholecystectomy, compared with the reference cohort, was 1.01 (95% confidence interval 0.90-1.12) and after 10 years or more follow-up it was 0.94 (0.79-1.10). It is highly improbable that the short-term associations between cholecystectomy and gastrointestinal cancers are causal, and we conclude that cholecystectomy does not cause cancer.
authors.affiliation: Unit of Health-Care Epidemiology, Department of Public Health, University of Oxford Old Road Campus, Old Road, Oxford OX3 7LF, UK. michael.goldacre@dphpc.ox.ac.uk
authors.forename: M J
authors.initials: MJ
authors.lastname: Goldacre
authors.forename: J D
authors.initials: JD
authors.lastname: Abisgold
authors.forename: V
authors.initials: V
authors.lastname: Seagroatt
authors.forename: D
authors.initials: D
authors.lastname: Yeates
mesh_terms: D000328:Adult; D000368:Aged; D002763:Cholecystectomy / Q000009:adverse effects*; D015331:Cohort Studies; D005260:Female; D005770:Gastrointestinal Neoplasms / Q000453:epidemiology / Q000209:etiology*; D006801:Humans; D015994:Incidence; D008297:Male; D008499:Medical Records / Q000706:statistics & numerical data; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors