2020 Volume 34 Issue 4 Pages 657-662
Intraductal papillary neoplasm of the bile duct (IPNB) is considered as a counterpart of intraductal papillary mucinous neoplasm of the pancreas (IPMN), however, IPNB has not been re-evaluated based on the similarity of pathological findings to IPMN, occurrence site, mucin production, and so on. This caused unbalanced case collection, contributing to the differences of diagnosis, treatment and results. In this study, we proposed a new classification; the lesions which pathologically resembled IPMN, frequently occurred at intrahepatic and perihilar bile duct, and showed minimal invasion with good prognosis, might be diagnosed as Type 1, while those which slightly resembled IPMN, frequently occurred at the distal bile duct, did not produce mucin and showed invasion with poor prognosis, were classified as Type 2. There were significant differences in the serum levels of liver enzymes, and total bilirubin, mucin production, occurrence site, grade of invasion and cumulative survival rate between the two types. We have to validate the appropriateness of the classification.
