Pathological Features and Prognosis of Combined Hepatocellular and Cholangiocarcinoma by World Health Organization Classification
Shinichi Aishima, Yuichiro Kubo, Yuki Tanaka, Yoshinao Oda. Kyushu University, Fukuoka, Japan
Background: According to the World Health Organization (WHO) classification, combined hepatocellular and cholangiocarcinoma (CHC) include classical type and subtypes with stem cell features, however, these subtypes of CHC are not distinctive clinicopathologic entities and the prognosis for CHC with stem cell features is unknown.
Design: We selected CHC cases using morpholgoical and immunohistochemical approach using hepatocellular markers (Heppar1, AFP, Glypican3) and biliary markers (CK19, CA19-9, NCAM, mucin production). Based on the WHO classification, we classified 100 cases of CHC into classical type (n=69), subtypes with stem cell features (n=25), such as cholangiolocellular subtype (n=8) and intermediate-cell subtype (n=17), and unclassified type (n=6). Classical type tumors were further divided into hepatocellular carcinoma predominant type (Cl-HCC, n=47) and cholangiocarcinoma predominant type (Cl-CC, n=22). Then we compared CHC subtype and clinicopathologic features.
Results: Tumor size of intermediate-cell type is larger than other types. Cholangiolocellular subtype shows only one case with vascular invasion and no cases with intrahepatic metastasis. Cl-CC type, intermediate-cell type and unclassified type show frequent vascular invasion and intrahepatic metastasis.
|Variable||Classical type||Subtypes with stem cell features||Unclassified type||p-value|
|Tumor size, average||3.8cm||4.4cm||3.7cm||6.6cm||4.4cm||*|
|Vascular invasion (+)||40.4%||77.3%||12.5%||70.6%||66.7%||0.003|
|Intrahepatic metastasis (+)||29.8%||50%||0%||58.8%||66.7%||0.0131|
|Viral infection (+)||82.2%||72.7%||71.4%||52.9%||66.7%||N.S.|