Pathological changes of gallbladder mucosa induced by pancreaticobiliary reflux

Abstract

Objective To investigate pathologic changes of gallbladder mucosa induced by continuous pancreaticobiliary reflux(PBR) in the preliminary stage and occult PBR stage. Methods Female Syrian golden hamsters were assigned into four groups: PBR model group (established by surgery), the blank control group, PBR with BOP group (to induce gallbladder cancer) and the simple BOP group. In addition, 87 patients with normal pancreaticobiliary junction (NPBJ) who underwent cholecystectomy or percutaneous transhepatic cholecystoscopy for gallbladder stones were assigned into two groups based on the value of bile amylase (BA): PBR group and the control group. Pathological changes of gallbladder mucosa between groups were analyzed and compared. Results In PBR model group, the incidences of gallbladder epithelial hyperplasia, pyloric gland metaplasia, intestinal metaplasia and low-grade neoplasia were 6/6, 3/6, 4/6 and 2/6, respectively. The incidence of gallbladder epithelial hyperplasia in PBR model group (6/6) was significantly higher than that of the blank control group (0/5). Incidence of gallbladder cancer (3/6) and high-grade neoplasia(1/6) was higher in PBR with BOP group than in the simple BOP group(0/5). In the clinical study, 70.6%(24/34) patients in PBR group presented high BA value (>1 000 U/L). Significantly higher occurrence of low-grade neoplasia can be observed in this group (73.5%, 25/34) compared with the control group (24.5%, 13/53, P<0.05). Conclusion Gallbladder mucosal hyperplasia and the tendency of high incidence of metaplasia can be detected in the preliminary stage of continuous PBR. High probability of gallbladder carcinoma or high-grade neoplasia can be induced with BOP in PBR model hamsters. Occult PBR can lead to low-grade cell dysplasia and therefore may be the factor of gallbladder malignancy. Key words: Gallbladder neoplasms; Pancreaticobiliary reflux(PBR); Gallbladder mucosa; Pathologic changes