Supplementary table 1. Biliary tract cancer codes used in the study.

HICDA code ICD-9 Code Cholangiocarcinoma (intrahepatic bile duct) (1551211) Malignant Neoplasm Of Intrahepatic Bile Ducts(155.1) Tumor, Klatskin (1551220) Malignant Neoplasm Of Extrahepatic Bile Ducts (156.1) Neoplasm, Malignant, Hepatic Bile Duct, Primary (1561410) Malignant Neoplasm of Ampulla of Vater (156.2) Neoplasm, Malignant, Common Bile Duct, Primary (1561210) Malignant Neoplasm Of Gall Bladder (156.0) Neoplasm, Malignant, Ampulla Of Vater, Primary (1562111) Malignant Neoplasm of Other Specified Sites of Gall Bladder And Extrahepatic Bile Ducts (156.8) Neoplasm, Malignant, Biliary, NOS, Primary (1569110) Malignant Neoplasm of Biliary Tract Part Unspecified Site (156.9) Neoplasm, Malignant, Gall Bladder, Primary (1560110) History OF, Malignancy, Bile Duct (34088-120) History OF, Malignancy, Ampulla OF Vater (34088-121) History Of, Malignancy, Gall bladder (34088-140)

HICDA, Hospital International Classification of Disease Adaptation; ICD, International Statistical Classification of Diseases and Related Health Problems Supplementary table 2. Comparison of survival between patients received curative resection versus others.*

Curative resection Others P values Median survival in months ICC . 2.8 0.02 Perihilar CCA 54.0 4.2 <0.01 CBD CCA 30.0 7.8 0.10 Ampulla of Vater 25.2 5.7 0.02 GB cancer 53.9 2.0 <0.01 Overall 49.7 3.7 <0.01

ICC, intrahepatic cholangiocarcinoma; CCA, cholangiocarcinoma; CBD, common bile duct; GB, gall bladder Median survival of patients received curative resection in ICC was incalculable due to the insufficient number of death.

.*These data do not necessarily prove that surgical resection improves survival. A large part of the differences is attributable to the stage of disease at presentation.