Impact of pancreatobiliary reflux in normal pancreatobiliary junction on gallbladder

Abstract

Objective To explore the impact of pancreatobiliary reflux （PBR） in normal pancreato- biliary junction on gallbladder. Methods A total of 54 patients receiving cholecystectomy for gallbladder diseases underwent uhrasonography to evaluate the thickness of gallbladder wall, inner layer and gallbladder wall blood flow before operation. The bile juice was sampled during ERCP in 45 patients with common bile duct stone and during cholecystectomy in 9 patients to detect amylase level. All patients with normal panere- atobiliary junction enrolled in the study were assigned into PBR group （ n = 24 ） and controlled group （ n = 30） according to their bile amylase level. Resected gallbladder specimens were examined histopathologically and then tested for expression of COX2, Ki-67 and p53 immunohistochemically. Results PBR group in- eluded 20 cases of cholelithiasis and 4 gallbladder polyp, among which 23 were occult PBR （OPBR） and 1 high confluence of pancreatobiliary ducts （ HCPBD）, which was similar to pancreatobiliary maljunction （PBM） pathologically. The control group recruited 28 cases of cholelithiasis and 2 gallbladder polyp. There were no differences in frequency of inflammation, hyperplasia, metaplasia or expression of p53 between the two groups （ p 〉 0.05 ） , while higher presence of dysplasia and higher expression of COX2 and Ki-67 were seen in PBR group （ p 〈 0.05）. Conclusion In patients with OPBR, although hyperplasia and metaplasia in gallbladder epithelium were similar to those induced by cholelithiasis, dysplasia and active proliferation might relate to progress to malignancy. Key words: Gallbladder; High confluence of pancreatobiliary ducts; Occult ancreatobiliary reflux; Biliary amylase