Association of Endoscopic Sphincterotomy or Papillary Balloon Dilatation and Biliary Cancer: A Population-Based Cohort Study.

Endoscopic sphincterotomy (EST) and endoscopic papillary balloon dilatation (EPBD) have become the main therapeutic procedures in the treatment of biliary and pancreas disease. The risk of cholangiocarcinoma (CCA) is not well investigated among post-EST/EPBD patients with benign diseases, particularly in Asia population. A retrospective nationwide cohort study using data from Taiwan's National Health Insurance Research Database (from January 1, 1998 through December 31, 2010) was conducted. Among patients with history of biliary stone with cholangitis, there were 17,503 patients in the EST/EPBD cohort and 69,998 subjects in the comparison. The incidence rate ratio was calculated using the Poisson regression model. Multivariable Cox proportional hazard models, adjusted for potential confounding factors, were used to assess the risk of developing CCA associated with endoscopic EST/EPBD. The cumulative incidences of CCA in the 2 cohorts were calculated using Kaplan-Meier analyses, and differences between the survival curves of the 2 cohorts were analyzed using a log-rank test. The overall incidence of CCA in the EST/EPBD cohort was higher than in the controls (1.36 vs 7.37 per 1000 person-years, IRR = 5.40, 95% CI = 5.15-5.67), with an adjusted HR of 4.41 (95% CI = 3.86-5.04). There were no CCA occurrences among patients receiving EST over the follow-up period 3 year after EST performed. The cumulative incidence of extrahepatic CCA seemed to be little growing in patients receiving EPBD. The cumulative incidence of intrahepatic CCA was also steady increasing in patients treated with EPBD and was more than patients receiving EST 10 years after EPBD by Kaplan-Meier analysis. In the population-based cohort study, EST is not associated with a long-term risk of intrahepatic and extrahepatic CCA. The risk of CCA for EPBD needs further investigation.