Gallbladder Cancer in the 21st Century

Table 4

TNM staging.

Stage	T-stage	N-stage	M-stage
0		N0	M0
I	T1	N0	M0
II	T2	N0	M0
IIIA	T3	N0	M0
IIIB	T1, T2, T3	N1	M0
IVA	T4	N0, N1	M0
IVB	Any T	Any N	M1
	Any T	N2	M0

Primary Tumour (T): T_is Carcinoma in situ; T₁ Tumour invades lamina propria (a) or muscular layer (b); T₂ Tumour invades perimuscular connective tissue; T₃ Tumour perforates serosa and/or invades liver and/or other adjacent organs (stomach, duodenum, colon, pancreas, and extrahepatic bile ducts); T₄ Tumour invades main porta vein or hepatic artery or multiple extrahepatic organs.
Regional Lymph Nodes (N): N₀ No regional lymph node metastasis; N₁ Metastases to nodes along cystic duct, common bile duct, hepatic artery, and/or portal vein; N₂ Metastases to periaortic, pericaval, superior mesenteric artery, and/or celiac artery nodes.
Distant Metastasis (M): M₀ No distant metastasis; M₁ Distant metastasis.