IDH3A and cholangiocarcinoma: Since the Food and Drug Administration (FDA)’s approval of the isocitrate dehydrogenase (IDH) 1 inhibitor ivosidenib in August 2021, there has been increasing interest in targeted therapy for CCA patients harboring mutations in fibroblast growth factor receptor (FGFR) 2, neurotrophic receptor tyrosine kinase (NTRK), B-raf kinase (BRAF), and HER2.