IDH1 and cancer: Mutations in IDH1/2 lead to accumulation of the oncometabolite 2-hydroxyglutarate (2-MG), inducing epigenetic changes in the tumors such as DNA hypermethylation and altered expression of chromatin remodelers.19–21 On the other hand, FGFR alterations, most commonly FGFR2 fusions, are responsible for the activation of various downstream-signaling pathways, including RAS/RAF/MEK, JAK/STAT, and PI3L/AKT pathways, which contribute to malignant transformation and cancer progression.22