Cholangiocarcinoma: Morphologic Classification According to Growth Pattern and Imaging Findings

Various terminology and classifications have been used to describe the pathologic and radiologic appearance of cholangiocarcinoma and each describes some specific aspects of the tumor. However, some of this terminology and classifications are ambiguous and therefore confusing. Eggel classified cholangiocarcinomas as nodular, massive and diffuse, as with hepatocellular carcinoma. Rosai classified cholangiocarcinoma as nodular, Sclerosing and polypoid. Weinbren and Mutum classified into three types: nodular, sclerosing, and papillary. In the radiologic literature, hilar and extrahepatic cholangiocarcinoma have been classified as exophytic, infiltrating and polypoid (or papillary).

Based on its growth characteristics, a new classification has been proposed by the Liver Cancer Study Group of Japan, with tumors being classified as mass-forming, periductal-infiltrating, and intraductal-growing types. Mass-forming intrahepatic cholangiocarcinoma shows a large, well-defined, irregular mass with frequent satellite nodules, periductal-infiltrating cholangiocarcinoma results in obliteration of the bile ducts and proximal dilatation without an identifiable mass, and intraductal-growing cholangiocarcinoma presents with focal or segmental bile duct dilatation with or without visible intraductal papillary tumors. Mass-forming extrahepatic cholangiocarcarcinoma results in bile duct obstruction by a small mass, periductal-infiltrating cholangiocarcinoma produces segmental or diffuse, concentric thickening of the wall of the bile ducts without a focal mass, and intraductal-growing chalangiocarcinoma produces bile duct dilatation with single or multiple, papillary intraductal masses. This classification is considered to be the most reasonable because it describes the groß appearance, growing characteristics, biological behavior, and prognostic implication for patients and because it is helpful for radiologic interpretation. According to this new classification, the exophytic or nodular type matches the mass-forming, the infiltrating or sclerosing type matches the periductal-infiltrating, and the polypoid or papillary type matches the intraductal-growing type.

The prognosis of mass-forming and periductal-infiltrating cholangiocarcinomas is generally unfavorable, while intraductal-growing cholagniocarcinoma has a much better prognosis after surgical resection. Precise characterization of these tumors in terms of their growth pattern and staging is mandatory for optimal treatment planning and in order to determine the prognosis. Surgical resection should be tailored depending upon the morphologic type as well as the stage of the tumors. In this regard, the morphologic classification of cholagniocarcinoma.

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Die Morphologische Klassifikation des Gallengangs-CA anwenden