Avapritinib in the Treatment of Unresectable or Recurrent Metastatic GIST Non-exon18 Mutations of PDGFRA

Inclusion Criteria: * Patients who are aged ≥ 18 years. * Gastrointestinal stromal tumors confirmed by histopathological examination, and CD- and/or DOG-1-positive by immunohistochemistry. * Presence of mRECIST v1.1-compliant lesions with at least one measurable lesion (non-lymphadenopathy ≥1.0 cm or ≥2-fold scan slice thickness). * Treatment with Avapritinib. * Patients with an Eastern Cooperative Oncology Group Performance Status (ECOG PS) of 0 to 2 at screening. * Patient informed consent and signed written consent form. * The patient was compliant and voluntarily scheduled for follow-up, treatment, laboratory tests, and other study procedures. Exclusion Criteria: * KIT or PDGFRA wild type. * Failure to complete continuous atorvastatin for at least 15 days due to intolerability or disease progression. * Other serious acute or chronic physical or mental problems, or laboratory abnormalities, may increase the risk associated with participation in the study or use of drugs, or interfere with the judgment of the study results and, in the judgment of the investigator, are not considered appropriate for participation in the investigator.