Cholecystectomy and carcinoma of the colon. An experimental study.

The influence of cholecystectomy on the development of carcinoma of the colon is investigated. The experimental results show a significantly increased rate of carcinoma of the colon induced by subcutaneous injection of 1,2-Dimethylhydrazin (DMH) in the mouse after cholecystectomy. After 10 weekly injections of 15 mg/kg DMH, 70% of the animals with cholecystectomy developed carcinoma. Only 16% of the mice with similar treatment but without cholecystectomy had carcinoma. The cocarcinogenic effect of cholecystectomy is assumed to be due to the increased production of secondary bile salts by the colonic bacteria and the lacking of the resorptive function of the gallbladder for some carcinogenic substances passing through the liver. The background of this experimental studies are the clinical findings that 10% of patients with carcinoma of the large bowel had previous cholecystectomy.