Optimizing outcomes and personalizing care with targeted agents in advanced cholangiocarcinoma

Traditional chemotherapy and immunotherapy-based systemic treatments for locally advanced or metastatic cholangiocarcinoma have been associated with poor clinical outcomes driven partly by molecular heterogeneity promoting early treatment resistance and a higher toxicity profile associated with these regimens. Few patients are eligible for upfront surgical resection and clinical studies have been traditionally difficult to conduct due to the orphan nature of this disease. However, increasing use of genomic profiling in clinical practice have led to active investigations of aberrant albeit promising mechanistic therapeutic targets such as IDH-1, FGFRs, BRAF^V600E, HER-2 and NTRK. This review article aims to highlight the complex genomic landscape of this difficult-to-treat disease, followed by a discussion of evidence-based biological mechanisms that can be actioned using targeted agents. We explore the clinical rationale behind a targeted therapeutic strategy, the role of liquid biopsies in guiding clinical decisions and future treatment pathways for cholangiocarcinoma management. We also discuss the challenges and opportunities originating from recent clinical trials evaluating targeted treatments and our own institutional experience at UCLH that have aimed to address some of these biological complexities and have translated into improved patient outcomes via effective molecularly driven patient selection strategies. We also provide perspectives on emerging novel, next generation targeted inhibitors overcoming treatment resistance to previous targeted agents with demonstrated clinical value in a challenging patient population.