Negative correlation between cholecystectomy and the subsequent development of large bowel carcinoma in a low-risk Japanese population.

The incidence of previous cholecystectomy in a series of 541 patients with colorectal cancer and 1832 patients with stomach cancer was studied. Five patients (0.92 percent) with colorectal cancer and eight (0.44 percent) with stomach cancer had undergone previous cholecystectomy. To avoid biases in the two groups of patients, 416 pairs of patients, comparable in sex, age, and time of admission for cancer treatment, were matched from each group to compare the number of patients who had undergone previous cholecystectomy. Within these matched pairs, three patients with colorectal cancer and two with stomach cancer had histories of cholecystectomy. Hence, no substantial difference was noted between the two groups. In a follow-up study of 461 patients who had undergone cholecystectomy for gallstones, large bowel carcinoma and stomach carcinoma developed in one and six patients, respectively, during an observation period of four to 36 years. The ratio of patients with large bowel cancer to those with stomach cancer observed in this survey was almost equal to the value estimated for the population of Tottori Prefecture, where the majority of the patients reside. The incidence of large bowel carcinoma is not increased among cholecystectomized patients in a low-risk Japanese population.