Organization

Field Name

ID

Required

KCR

EOD Schema Discriminator 1

30122

 

SEER

Schema Discriminator 1

3926

 

Note A schema discriminator is used to discriminate for primary site C240 (extrahepatic bile ducts) for the subsite in which the tumor arose.

  • Chapter 24 Gallbladder (see code 3)
    Per AJCC 8th edition, the gallbladder tapers into the cystic duct
  • Chapter 25 Perihilar Bile Ducts (see codes 1, 5, 6, 9)
    Per AJCC 8th edition, perihilar (or proximal) cholangiocarcinomas involve the main biliary confluence of the right and left hepatic ducts and comprise 50-70% of all cases of bile ducts carcinomas
  • Chapter 26 Distal Bile Ducts ( see codes 4, 7)
    Per AJCC 8th edition, these tumors have their center located between the confluence of the cystic duct and common hepatic duct and the Ampulla of Vater (excluding ampullary carcinomas.)

Code

Description

Disease

1

Perihilar bile duct(s)
Proximal extrahepatic bile duct(s)
Hepatic duct(s)

25: Perihilar Bile Ducts

3

Cystic bile duct; cystic duct

24: Cystic Duct

4

Distal bile duct
Common bile duct
Common duct, NOS

26: Distal Bile Ducts

5

Diffuse involvement
More than one subsite involved, subsite of origin not stated

25: Perihilar Bile Ducts

6

Stated as middle extrahepatic bile duct
AND treated with combined hepatic and hilar resection

25: Perihilar Bile Ducts

7

Stated as middle extrahepatic bile duct
AND treated with pancreaticoduodenectomy

26: Distal Bile Ducts

9

Extrahepatic bile ducts, NOS

25: Perihilar Bile Ducts