FGFR2 and cholangiocarcinoma: Currently, FGFR2 fusion mutations (approximately 10%–20%) and IDH1 gene mutations (approximately 15%–20%) are the most common mutations in CCA and have been widely used in clinical practice with FDA-approved targeted therapies (Abou-Alfa et al., 2020a; Uson Junior and Borad, 2022).