IDH1 and cholangiocarcinoma: The European Society for Medical Oncology Scale for Clinical Actionability of Molecular Targets (ESCAT) ranked genomic alterations in advanced cholangiocarcinoma based on therapeutic implications, and level I alterations included IDH1 mutations, FGFR2 fusions, microsatellite instability-high (MSI-H), and NTRK fusions [33].