title: Response to sunitinib of a gastrointestinal stromal tumor with a rare exon 12 PDGFRA mutation.
abstract: BACKGROUND
  Gastrointestinal stromal tumors (GISTs) are commonly driven by activating mutations in either KIT or PDGFRA. Importantly, different mutations within these two genes can lead to very different levels of sensitivity or resistance to kinase inhibitor therapy. Due to rarity, sensitivity or resistance of exon 12 PDGFRA mutant GIST to kinase inhibitor therapy is not well defined.
  
  
  METHODS
  We report the case of a patient with a PDGFRA exon 12 mutated GIST. The patient experienced a very good response to imatinib in the neoadjuvant setting, but then relapsed while still on adjuvant imatinib. In this patient, we report a dramatic response to second line treatment with sunitinib, with complete resolution of two liver lesions at the time of first restaging.
  
  
  CONCLUSIONS
  This is the first report detailing a response to treatment with sunitinib of a gastrointestinal stromal tumor with an uncommon exon 12 PDGFRA mutation. Based on the observed efficacy, GIST patients with this rare molecular subtype should be considered for sunitinib therapy.
authors.affiliation: Sarcoma Department, Moffitt Cancer Center, 12902 Magnolia Drive, Tampa, FL 33612 USA.
authors.forename: Andrew S
authors.initials: AS
authors.lastname: Brohl
authors.affiliation: Department of Pathology, Icahn School of Medicine at Mount Sinai, New York, NY USA.
authors.forename: Elizabeth G
authors.initials: EG
authors.lastname: Demicco
authors.affiliation: Zwanger-Pesiri Radiology, Lindenhurst, NY USA.
authors.forename: Karen
authors.initials: K
authors.lastname: Mourtzikos
authors.affiliation: Hematology and Medical Oncology, Icahn School of Medicine at Mount Sinai, New York, NY USA.
authors.forename: Robert G
authors.initials: RG
authors.lastname: Maki
keywords: GIST; Imatinib; PDGFRA; Sunitinib