...1.Age 18-75 years old, male or female; 2.GIST tumor is primary, no distant metastasis was found in preoperative examination and intraoperative exploration; 3.No targeted drug neoadjuvant therapy before operation; 4.Accepted Radical R0 surgical resection; 5.Postoperative pathologically confirmed soft tissue tumor, in line with GIST; 6.Genetic testing (first- or second-generation sequencing) confirmed PDGFRα Exon18 D842V mutation, and the remaining sites were detected c-kit (Exon-9, Exon-11, Exon-13, Exon-17) and PDGFRα (Exon-12) have no mutation; 7.Have understood and signed the informed consent....

A 49-year-old male with duodenal GIST and liver metastases (c-KIT exon 11 mutation positive)...He had a partial response at 2 months of therapy with avapritinib and stable disease at 5 months. However, he had a progression at 8 months and a grade 4 subdural hemorrhage.