Prophylactic excision of the gallbladder and bile duct for patients with pancreaticobiliary maljunction

Hypothesis: Pancreaticobiliary maljunction (PBM) is a high-risk factor for biliary tract carcinogenesis because of a continuous reflux of pancreatic j uice into the biliary tract. It remains to be disclosed whether we should p erform prophylactic excision of gallbladders and bile ducts. Design: A person-year method. Setting: A university hospital. Patients: We studied 68 patients with PBM treated between August 1, 1974, a nd December 31, 1999. Main Outcome Measures: Relative risks (observed number-expected number rati os) of gallbladder and bile duct carcinomas according to type of bile duct dilation tie, cystic dilation, diffuse dilation, and nondilation). Results: Observed number-expected number ratios of gallbladder carcinomas w ere high: 291.3 in 43 patients with cystic dilation, 167.2 in 16 patients w ith diffuse dilation, and 419.6 in 7 patients with nondilation. Observed nu mber-expected number ratios of bile duct carcinomas were 194.2 in 43 patien ts with cystic dilation before surgery and 142.8 in 39 patients with cystic dilation after long postsurgical follow-up. All these values were statisti cally significant (P<.01). Conclusions: The gallbladder carries a high risk for carcinogenesis in all types of dilation in patients with PBM. The bile duct carcinomas of PBM wer e exclusively identified by the type of cystic dilation. Prophylactic chole cystectomy should be recommended for all dilation types, and prophylactic e xcision of bile ducts including cholecystectomy should be performed in pati ents with PBM and cystic dilation. Complete excision of extrahepatic dilate d bile ducts and careful follow-up for carcinogenesis in residual dilated b ile ducts should be recommended for patients with PBM and cystic dilation.