Biliary tract cancer: ESMO Clinical Practice Guideline for diagnosis, treatment and follow-up

•This ESMO Clinical Practice Guideline provides key recommendations for managing biliary tract cancer.•The guideline covers clinical and pathological diagnosis, staging and risk assessment, treatment and follow-up.•A treatment and management algorithm for locoregional and advanced/metastatic disease is provided.•ESCAT scores are given to describe the evidence level for genomic alterations as biomarkers for using targeted therapies.•Recommendations are based on available scientific data and the authors’ collective expert opinion.