Cholecystectomy as a risk factor for gastric cancer. A cohort study.

Epidemiological findings suggest that gallstone disease and some frequent human cancers share common risk factors. In the present historical prospective cohort study, comprising 16,773 patients who had undergone cholecystectomy 12-15 years previously, the risk of developing gastric cancer was investigated. The total number of observed gastric cancers (89) was very close to the expected number (88), giving a relative risk (RR) of 1.01. A significantly increased risk (P less than 0.01; RR = 2.67) of developing gastric cancer was found during the first year after cholecystectomy, and this increase was judged to be due to cancers that were present but overlooked at the time of cholecystectomy. Subgrouping according to age at surgery revealed a tendency towards a lower risk in patients operated on before the age of 70 years. It is concluded that our data do not support the hypothesis that there are common risk factors for gallstones and cancer, and cholecystectomy does not seem to be associated with an increased risk of gastric cancer within 15 years after this operation.