Does Biliopancreatic Diversion Carry Increased Risk for Colorectal Cancer? A Cohort Study

BACKGROUND: Because of the rearrangement of the gastrointestinal tract, biliopancreatic diversion (BPD) could lead to an increased risk of colorectal cancer caused by possible carcinogenetic action of the unabsorbed food and bile acid on colonic mucosa. METHODS: The incidence of colorectal cancer in 1,898 obese subjects submitted to BPD from May 76 to July 2002 with a minimum follow-up of 5 years was retrospectively evaluated. RESULTS: Among 28,811 person-years, seven cases of colorectal cancer were detected, for an overall incidence of 29.4 per 100,000, which is not different from that observed in the general Italian population, and lower than that reported for obese and type 2 diabetes patients. Logistic regression model suggests that occurrence of colorectal cancer is positively related to the time elapsed from BPD. CONCLUSION: This study indicates that BPD does not carry any increased risk for colorectal cancer. The complete postoperative restoration of insulin sensibility could exert a valuable protective action.