Comprehensive genomic profiling of extrahepatic cholangiocarcinoma reveals a long tail of therapeutic targets

Aim We queried whether extrahepatic cholangiocarcinoma featured clinically relevant genomic alterations that could lead to targeted therapy. Methods Comprehensive genomic profiling by hybridisation capture of up to 315 genes was performed on 99 clinically advanced extrahepatic cholangiocarcinoma. Results There were 60 male and 39 female patients with a median age of 60.5 years. A total of 400 alterations were identified (mean 4.0; range 0-13) in 84 genes. Eighty-two (83%) of extrahepatic cholangiocarcinoma patients featured at least one clinically relevant genomic alterations including KRAS (43%); ERBB2 (9%), PTEN (7%); ATM and NF1 (6%) and CCND1, FBXW7, GNAS, MDM2 and NRAS (all at 5%). BRAF, BRCA2, CDK4, CDK6, FGFR1, FGFR3, PTCH1, RAF1 and STK11 were each altered in a single patient. No IDH1/2 mutations or FGFR2 gene fusions were identified. Conclusions Comprehensive genomic profiling of extrahepatic cholangiocarcinoma differs significantly from intrahepatic cholangiocarcinoma and pancreatic adenocarcinoma, and reveals diverse opportunities for the use of targeted therapies.