Unresectable biliary tract cancer: Current and future systemic therapy.

For decades, treatment of advanced biliary tract cancer (BTC) was confined to the use of chemotherapy. In recent years however, the number of therapeutic options available for patients with unresectable BTC have drastically increased, with immunotherapy and targeted treatment gradually joining the ranks of guideline-recommended treatment regimens. The aim of the present review is to summarise the current knowledge on unresectable BTC focusing on epidemiology, anatomical distribution and current strategies for systemic treatment. We further outline ongoing clinical trials and provide an outlook on future therapeutic interventions. In the realm of gastrointestinal malignancies, the increasing number of systemic treatment options for BTC is finally delivering on the longstanding commitment to personalised oncology. This emphasises the need for considering a comprehensive genomic-based pathology assessment right from the initial diagnosis to fully leverage the expanding array of therapeutic options that have recently become accessible.