KIT and gastrointestinal stromal tumor: Imatinib mesylate (Gleevec; Novartis, Basel, Switzerland) [10] (IM), a tyrosine kinase inhibitor of the constitutional activity of c-kit and PDGFR-α [11], has revolutionized the management of unresectable, recurrent, and metastatic GIST, with significant improvement on progression-free survival (PFS) and overall survival (OS) [12–16].