title: Metastatic Gastrointestinal Stromal Tumor to the Skull.
abstract: BACKGROUND
  Gastrointestinal stromal tumors (GISTs) arising from the interstitial cells of Cajal along the gastrointestinal tract rarely metastasize to the central nervous system (CNS) but require aggressive multimodal therapies when they do. We present a case of recurrent GIST metastasis to the skull and review the literature on management, including the role of molecular profiling in determining adjuvant treatment.
  
  
  METHODS
  A 64-year-old woman presented with an enlarging palpable mass over her right eye. Magnetic resonance imaging revealed an enhancing T1-hypointense, T2-hyperintense right frontal calvarial lesion with lytic features on computed tomography. Pathology confirmed metastatic GIST to the skull with dural involvement. Molecular profiling revealed a mutation in exon 11 of KIT in her primary tumor, while the skull metastasis harbored an additional mutation in exon 17 associated with acquired drug resistance.
  
  
  CONCLUSIONS
  We review the epidemiology of GIST metastases and discuss potential reasons for its rare presentation to the CNS. Additionally, we highlight the diagnostic and prognostic value of molecular profiling for metastatic GIST, as well as its influence in arbitrating targeted molecular inhibitor therapy. Evolving molecular signatures, associated with treatment resistance, may play a pivotal role in future integration with multimodality treatment strategies for CNS GIST.
authors.affiliation: Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Saksham
authors.initials: S
authors.lastname: Gupta
authors.affiliation: Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: Wenya Linda
authors.initials: WL
authors.lastname: Bi
authors.affiliation: Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA. Electronic address: idunn@partners.org.
authors.forename: Ian F
authors.initials: IF
authors.lastname: Dunn
mesh_terms: D005260:Female; D005770:Gastrointestinal Neoplasms / Q000473:pathology* / Q000601:surgery; D046152:Gastrointestinal Stromal Tumors / Q000473:pathology* / Q000601:surgery; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D019292:Skull Base Neoplasms / Q000000981:diagnostic imaging / Q000532:radiotherapy / Q000556:secondary* / Q000601:surgery*
keywords: CNS metastasis; Gastrointestinal stromal tumor; Skull lesions; Targeted inhibitors; c-Kit