PDGFRA and gastrointestinal stromal tumor: Ripretinib, the first FDA-approved broad-spectrum kinase inhibitor for fourth-line GIST treatment (Ripretinib for gastrointestinal stromal tumours, 2021), uniquely targets both the kinase activation loop and switch pocket, effectively suppressing diverse resistance mutations including KIT and PDGFRA variants (Goggin et al., 2022).