Extrahepatic biliary cancer: New staging classification

Table 4 Extrahepatic bile duct tumors (American Joint Commission on Cancer staging 6th edition)

Tumor	TNM classification
T1	Tumor confined to bile duct histologically
T2	Tumor beyond the wall of bile duct
T3	Tumor invades liver, GB, pancreas, and/or ipsilateral PV (R or L) or hepatic artery (R or L)
T4	Tumor invades main portal vein or its branches bilaterally, common hepatic artery, or adjacent structures (colon, stomach, duodenum, abdominal wall)
Node
N0	No regional lymph node metastasis
N1	Regional lymph node metastasis (including hilar, celiac, superior mesenteric, periduodenal and peripancreatic)
Metastasis
M0	No distant metastasis
M1	Distant metastasis
Tumor stage	AJCC staging 6th edition
Stage IA	T1, N0, M0
Stage IB	T2, N0, M0
Stage IIA	T3, N0, M0
Stage IIB	T1 or T2 or T3, N1, M0
Stage III	T4, any N, M0
Stage IV	Any T, any N, M1

T: Tumor; N: Node; M: Metastases; GB: Gallbladder; PV: Pulmonary vein; AJCC: American Joint Commission on Cancer.