PDGFRA and gastrointestinal stromal tumor: The most common mutation is c-KIT exon 11, followed by c-KIT exon 9, while mutations in c-KIT exons 13, 14, 17, and 18 are rare.[17,18] In recent years, the application of tyrosine kinase inhibitors targeting c-KIT and PDGFRA genes, such as imatinib, has achieved a breakthrough in the treatment of GIST, with 83% to 89% of patients with advanced GIST benefiting from imatinib.[19,20] Given that the therapeutic effect of imatinib is directly related to the mutation status, it is necessary to conduct mutation analysis by immunohistochemistry before imatinib treatment.