Early Recurrence Following Resection of Distal Cholangiocarcinoma: A New Tool for the Toolbox

Clinical research in biliary tract cancer presents significant challenges. The relatively low and highly variable incidence of biliary tract adenocarcinoma, compared with other primary adenocarcinomas, requires that three anatomic subtypes of cholangiocarcinoma (intrahepatic, perihilar, and distal) and gallbladder carcinoma be pooled to achieve sufficient power to test hypotheses. The landmark ABC-02 trial, which established cisplatin and gemcitabine as the preferred systemic therapy for advanced disease, included 149 (36.3%) gallbladder tumors, 241 (58.8%) undifferentiated bile duct tumors, and 20 (4.9%) ampullary tumors.1 More recently, the BILCAP study, which established capecitabine as the standard adjuvant regimen, included 84 (18.8%) intrahepatic, 128 (28.6%) perihilar, and 156 (34.9%) distal cholangiocarcinomas (DCCs), and 79 (17.7%) gallbladder carcinomas.2 Attempts to overcome these issues with administrative data are fraught with error, as frequent changes to the International Classification of Diseases and Related Health Problems (ICD) codes for cholangiocarcinoma over time have led to miscoding of anatomic subtypes, and inconsistent code utilization globally.3 …