PDGFRA and gastrointestinal stromal tumor: Imatinib mesylate (IM), an RTK inhibitor targeting the mutant forms of KIT and PDGFRA, is the first-line therapy in the neoadjuvant setting for treatment of unresectable and metastatic GIST which aims to downstage the tumor prior to resection and in the adjuvant setting for patients with a high risk of recurrence for IM-sensitive tumors [5,6,7].