Intraductal papillary neoplasm of the bile duct (IPNB) is a variant of bile duct tumors characterized by papillary growth within the dilated bile duct lumen and secretion with a large amount of mucins. IPNB is an intraductal papillary cancer of the bile duct or a preinvasive lesion classified by the 2010 World Health Organization (WHO) classification. Although the specific etiology and pathogenesis are unclear, IPNB is known to two major risk factors: hepatoliathiasis and clonorchiasis. The clinical manifestations of IPNB include intermittent abdominal pain, acute cholangitis and obstructive jaundice. Results of laboratory test show abnormal liver function resulting from obstruction of bile duct, but it′s not specific. The most common imaging findings for IPNB are bile duct dilatation and intraductal masses. Computed tomography, magnetic resonance image and cholangiography are usually performed to access tumor location and extension. According to morphology of the tumor epithelial cells, IPNB are classified into the pancreticbiliary, intestinal, gastric and oncocytic types. The surgical resection is a major treatment of IPNB. In principle, IPNB should be resected in a manner similar to that employed for other types of intrahepatic cholangiocarcinomas and extrahepatic bile duct carcinomas. The type of surgical procedure for IPNB depends upon tumor location and extension. Although several investigations have been conducted for illuminating molecular genetic changes during the deve-lopment and progression of IPNB, the specific mechanism is still not clear, and further study is needed.

Bile duct neoplasms; Papillary neoplasms; Mucin core proteins