The classification applies to carcinomas of the extrahepatic bile ducts of perihilar localization (Klatskin tumour). Included are the right, left and common hepatic ducts. Perihilar cholangiocarcinomas are tumours located in the extrahepatic biliary tree proximal to the origin of the cystic duct. The regional nodes are the hilar and pericholedochal nodes in the hepatoduodenal ligament. The pT and pN categories correspond to the T and N categories. Note pM0 and pMX are not valid categories.
EXTRAHEPATIC BILE DUCTS – PERIHILAR (ICD‐O‐3 C24.0)
Rules for Classification
Anatomical Sites and Subsites (Fig. 221)
Regional Lymph Nodes
TNM Clinical Classification
T – Primary Tumour
TX
Primary tumour cannot be assessed
T0
No evidence of primary tumour
Tis
Carcinoma in situ
T1
Tumour confined to the bile duct, with extension up to the muscle layer or fibrous tissue (Fig. 222)
T2a
Tumour invades beyond the wall of the bile duct to surrounding adipose tissue (Fig. 223)
T2b
Tumour invades adjacent hepatic parenchyma (Fig. 224)
T3
Tumour invades unilateral branches of the portal vein or hepatic artery (Fig. 225a)
T4
Tumour invades the main portal vein or its branches bilaterally; or the common hepatic artery; or the second‐order biliary radicals bilaterally; or unilateral second‐order biliary radicals with contralateral portal vein or hepatic artery involvement (Fig. 225b)
N – Regional Lymph Nodes
NX
Regional lymph nodes cannot be assessed
N0
No regional lymph node metastasis
N1
Metastases to 1 to 3 regional lymph nodes
N2
Metastases to 4 or more regional nodes
M – Distant Metastasis
M0
No distant metastasis
M1
Distant metastasis
TNM Pathological Classification
pM1
Distant metastasis microscopically confirmed
pN0
Histological examination of a regional lymphadenectomy specimen will ordinarily include 15 or more lymph nodes. If the regional lymph nodes are negative, but the number ordinarily examined is not met, classify as pN0.
Summary