Focal intrahepatic strictures: A proposal classification based on diagnosis-treatment experience and systemic review

Table 3 Pathological characteristics of focal intrahepatic strictures

No.	Pathological characteristics of FIHS and related lesions
	Location of dilated bile duct	Macroscopic					Microscopic
		Location of FIHS	Features of related lesions				Structure	Pathological diagnosis	Differentiation of malignant FIHS	Surgical margin
			Location of related lesions	Size (cm)	Color	Texture
1	B2, B3	Confluence of B2/B3	ICC: left lateral lobe	ICC: 0.8	Grey white	Jellylike	Tubulo-villous	Peritubular infiltrating type ICC; Partial mucinous adenocarcinoma	Moderate	-
2	-	-	-	-	-	-	-	-	-	-
3	B2, B3, B4	Confluence of B2/B3/B4	ASC: left lobe	ASC: 6.0 (Dilated bile ducts)	Grey white	Hard	Irregular nests of polygonal cells; intercellular bridges	ASC of liver; Hepatolithiasis	Moderate	-
4	B2, B3, B4	Confluence of B2/B3/B4	Hepatolithiasis: B2, B3, B4	Stones: 0.1-0.2	black brown	Hard	Lymphocytes, plasma cells, macrophages infiltration; Fibrosis	Cholangitis; Hepatolithiasis	N/A	N/A
5	-	-	-	-	-	-	Portal inflammation with edema, Fibrosis and proliferation	SD-PSC	N/A	N/A
6	-	-	-	-	-	-	Cloudy swelling of liver cells; cholestasis; inflammatory cell infiltration; proliferation of small bile ducts	AIH	N/A	N/A

FIHS: Focal intrahepatic strictures; ICC: Intrahepatic cholangiocarcinoma; SD-PSC: Small duct primary sclerosing cholangitisprimary; ASC: Adenosquamous carcinoma; B2: Bile duct of segment II; B3: Bile duct of segment III; B4: Bile duct of segment IV; AIH: Autoimmune hepatitis; N/A: Not applicable.