BACKGROUND: There may be an increased risk of colorectal cancer after cholecystectomy, but the literature is not consistent. It is also possible that any risk might be associated with gallstones rather than cholecystectomy. METHODS: In a prospective necropsy study of 8563 cases, all 219 cases of a previous cholecystectomy were pair-matched to subjects with gallstones and to subjects with a normal gallbladder. In a second study all 192 cases of colorectal cancer were pair-matched to cancer-free subjects. RESULTS: The odds ratio (OR) for developing colorectal cancer after cholecystectomy compared with a normal gallbladder was 1.0 (95% confidence interval, 0.30-3.34) and with unoperated gallstones was 0.88 (0.27-2.76). CONCLUSIONS: This study fails to support an association between cholecystectomy or gallstones and colorectal cancer. For those cases of colorectal cancer versus controls, the OR for previous cholecystectomy was 0.70 (0.23-2.04) and for gallstone disease was 0.93 (0.58-1.48).
BACKGROUND: There may be an increased risk of colorectal cancer after cholecystectomy, but the literature is not consistent. It is also possible that any risk might be associated with gallstones rather than cholecystectomy. METHODS: In a prospective necropsy study of 8563 cases, all 219 cases of a previous cholecystectomy were pair-matched to subjects with gallstones and to subjects with a normal gallbladder. In a second study all 192 cases of colorectal cancer were pair-matched to cancer-free subjects. RESULTS: The odds ratio (OR) for developing colorectal cancer after cholecystectomy compared with a normal gallbladder was 1.0 (95% confidence interval, 0.30-3.34) and with unoperated gallstones was 0.88 (0.27-2.76). CONCLUSIONS: This study fails to support an association between cholecystectomy or gallstones and colorectal cancer. For those cases of colorectal cancer versus controls, the OR for previous cholecystectomy was 0.70 (0.23-2.04) and for gallstone disease was 0.93 (0.58-1.48).