Significance of CD44s and CD44v6 Expression in Pancreaticobiliary Maljunction

Background/Aims: Pancreaticobiliary maljunction (PBM) is a high risk factor in biliary tract cancer. The relation of CD44s and CD44v6 expression in biliary epithelium with PBM and the carcinogenetic process was immunohistochemically examined. Methodology: One hundred and seven lesions were randomly selected from gallbladders and bile ducts, which were resected from 25 patients with PBM, and immunostaining for CD44s, CD44v6 and MIB-1 was carried out. Results: Among gallbladder lesions, cancerous lesions (dysplasia, cancer) had a higher immunoreactivity with statistical significance for CD44s and CD44v6 compared to non-cancerous lesions (normal, hyperplasia). In bile ducts as well, cancerous lesions had a higher immunoreactivity for CD44s and CD44v6. In both gallbladders and bile ducts, positive cases of CD44s and CD44v6 had a higher statistical significance of Ki-67 labeling index in comparison with negative cases. Conclusions: In biliary epithelium with PBM, CD44 was indicated to be strongly related to cancer progression via an increase of cellular proliferative potential.