Table 2.

Histological classification of cholangiocarcinoma

Based on histological differentiation
Well (> 95% of tumour composed of glands)
Moderately (50%-95% of tumour composed of glands)
Poor (5%-49% of tumour composed of glands)
Undifferentiated type (< 5% of tumor composed of glands)
Based on glandular features
Conventional type (bile duct type)
Small bile duct type (intrahepatic)
Large bile duct type
Cholangiocellular (intrahepatic)
Uncommon variants
Ductal plate malformation type (intrahepatic)
Lymphoepithelioma type
Clear cell type
Squamous/adenosquamous type
Mucinous carcinoma
Sarcomatoid
Signet ring carcinoma
Neuroendocrine
HCC-like

HCC: Hepatocellular carcinoma.