Avapritinib Therapy for Preoperative Treatment of Gastrointestinal Stromal Tumors with PDGFRA Mutation

Imatinib is still the first-line therapy for unresectable or recurrent/metastatic GIST [1, 2]. However, the number of cases that achieve complete remission has been unsatisfactory and a large number of patients who receive imatinib therapy suffer from primary or secondary resistance [3]. Approximately 5–10% of GIST harbor oncogenic mutations in the juxtamembrane domain or activation loop of platelet-derived growth factor receptor alpha (PDGFRA), a receptor tyrosine kinase that is highly homologous to KIT [4]. Most patients with PDGFRA gene mutation on exon 18, including the D842V subtypes, are highly resistant to imatinib (primary resistance), which is a major clinical difficulty for prescribing individual therapy [5–7]. Hence, it is necessary to discover novel targeted therapies for refractory GIST to improve patient prognosis and create better surgical opportunities [8].