Cystic and Micropapillary Neoplasm of Peribiliary Glands: Its Perspective to Cholangiocarcinogenesis

Abstract

Peribiliary glands are located around the extrahepatic and perihilar bile ducts and are reportedly involved in the development and the diseases of the hepatobiliary and pancreatic systems. In the glandular system, several pathological changes such as cystic dilatation, hyperplasia, and neoplasia have been identified. Cystic dilatation of microscopic size is not uncommon in the peribiliary glands. Rarely, cystic changes are accompanied by micropapillary epithelial proliferation within the glands. The cystic and micropapillary lesions of the peribiliary glands may have neoplastic features, and histological pictures resemble to those of branch-type intraductal papillary mucinous neoplasm of the pancreas other than the smaller size of ductal diameter. They may be precursors of biliary epithelial neoplasms involving intraductal papillary neoplasm of the bile duct as well as cholangiocarcinoma. Although the clinical significance of cystic and micropapillary lesions of the peribiliary glands remains uncharted, the recognition of the lesion seems to be important in biliary tract pathology when the biology and oncogenesis of biliary epithelial neoplasms are considered.