EXTRAHEPATIC BILE DUCTS – DISTAL (ICD‐O‐3 C24.0)

Rules for Classification

The classification applies to carcinomas of the extrahepatic bile ducts distal to the insertion of the cystic duct. Cystic duct carcinoma is included under gallbladder.

Regional Lymph Nodes

The regional lymph nodes are along the common bile duct, hepatic artery, back towards the coeliac trunk, posterior and anterior pancreaticoduodenal nodes, and nodes along the superior mesenteric artery.

TNM Clinical Classification

T – Primary Tumour

TX	Primary tumour cannot be assessed
T0	No evidence of primary tumour
Tis	Carcinoma in situ
T1	Tumour invades bile duct wall to a depth of less than 5 mm (Fig. 226)
T2	Tumour invades bile duct wall to a depth of 5 mm up to 12 mm (Fig. 226)
T3	Tumour invades bile duct wall to a depth of more than 12 mm (Fig. 227)
T4	Tumour involves the coeliac axis or the superior mesenteric artery (Fig. 228)

Schematic illustration of tumour invades bile duct wall to a depth of less than 5 mm. — **Fig. 226**

Schematic illustration of tumour invades bile duct wall to a depth of more than 12 mm. — **Fig. 227**

Schematic illustration of tumour involves the coeliac axis or the superior mesenteric artery. — **Fig. 228**

N – Regional Lymph Nodes

NX	Regional lymph nodes cannot be assessed
N1	Metastases to 1 to 3 regional nodes
N2	Metastases to 4 or more regional nodes

M – Distant Metastasis

M0	No distant metastasis
M1	Distant metastasis

TNM Pathological Classification

The pT and pN categories correspond to the T and N categories.

pM1	Distant metastasis microscopically confirmed

Note

pM0 and pMX are not valid categories.

pN0

Histological examination of a regional lymphadenectomy specimen will ordinarily include 12 or more lymph nodes. If the regional lymph nodes are negative, but the number ordinarily examined is not met, classify as pN0.