Selection of fibroblast growth factor receptor (FGFR) inhibitor for precision medicine. (A) Classification of FGFR inhibitors based on substrate specificities. *, FIIN-2 is for experimental use only. **, Severe adverse effects of ponatinib have been reported in patients with chronic myeloid leukemia. (B) Flow-chart for the choice of FGFR inhibitor in clinic. MPN, myeloproliferative neoplasm; Amp, gene amplification; OverE, overexpression; Fus, fusion. FGFR1/2/3 inhibitors and pan-FGFR inhibitors are applicable for human cancer with genetic alteration in FGFR1, FGFR2 or FGFR3. FGFR1/2/3 inhibitors are not the choice for patients with heart diseases, whereas pan-FGFR inhibitors are not the choice for patients with liver dysfunction. FGFR4 inhibitor is applicable for HCC with genetic alteration in FGF19.