CLINICOPATHOLOGICAL SPECTRUM OF RESECTED EXTRADUCTAL MASS-FORMING INTRAHEPATIC CHOLANGIOCARCINOMA

Background. The mode of tumor growth of intrahepatic cholangiocarcinoma (CC) varies considerably from patient to patient. This study describes the clinicopathologic variety of the extraductal mass-forming type of CC. Methods. Patients with CC characterized by an extraductal mass (n = 26) who underwent hepatectomy from 1976 through 1992 were clinicopathologically classified into three types: Type I(n = 7), no biliary stricture; Type II (n = 13), biliary stricture without jaundice; and Type III(n = 6), biliary stricture with jaundice. Results. Type I included three patients with microductular-trabecular arrangement and behavior reminiscent of hepatocellular carcinoma (high association with chronic liver disease, mild positivity for alpha-fetoprotein [AFP], no lymph node metastasis, but frequent intrahepatic metastasis), in contrast to the other typical cholangiocarcinoma. Hepatolithiasis was associated only with Type II CC. The serum positivity for AFP and carcinoembryonic antigen was much higher in Type I CC, whereas positivity of CA 19-9 was highest in Type III. Involvement of the portal vein, hepatic artery, or hepatic duct was most frequent in Type III CC, which necessitated resection of the extrahepatic bile duct and hepatectomy. Conclusion. The clinicopathologic behavior of intrahepatic CC differs considerably according to the presence or absence of stricture of the biliary tree. Thus, CC without biliary stricture behaves more like hepatocellular carcinoma, whereas CC with biliary stricture is more like hilar or extrahepatic bile duct carcinoma.