Table 1.

Main charactéristic of cholangiocarcinoma subtype.

Type	iCCA		eCCA
	Small Duct	Large Duct	d + p CCA
Cells of origin	Interlobular bile duct	Peribiliary glands	Cholangiocytes Peribiliary glands
morphology	Small duct with cubic cells and little mucosecretion	Large duct or papillae lined with mucus secreting columnar cells	Same than large duct iCCA
phenotype	Cytoplasmic expression of CK7 and CK19
	Expression of CRP, N-cadherin and CD56	Expression of S100P, MUC5AC and MUC6	Same than large duct iCCA
extension	High frequency of SN Low frequency of PNI Vascular invasion Metastatic lymph node	Low frequency of SN and high frequency of PNI Hepatic infiltration	Same than large duct iCCA
Molecular alterations	IDH1/2, BRCA1/2 and BAP 1 mutations, FGFR2 fusion	KRAS, TP53 mutations	Same than large duct iCCA with an higher frequency of KRAS mutations

iCCA: intrahepatic CC, eCCA: extrahepatic CC, CK: cytokeratin, CRP: c reactive protein, SN: satellite nodule, PNI: perineural invasion.