title: An IDH1-mutated primary gliosarcoma: case report.
abstract: The authors present the case of a primary gliosarcoma with an isocitrate dehydrogenase-1 (IDH1) mutation. A 75-year-old man presented with a 3-day history of multiple focal seizures and was found on MRI to have a 2.2-cm left parietal enhancing mass lesion. Brain MRI for tremor performed 8 years prior to this presentation was normal. En bloc resection revealed a high-grade glioma with sarcomatous components that was immunoreactive for the R132H variant of IDH1 by antibody. Gliosarcoma is a rare variant of glioblastoma that arises most frequently as a primary tumor, and has equal or worse survival and an increased propensity for extracranial metastases compared with other Grade 4 gliomas. In contrast, isocitrate dehydrogenase-1 and -2 mutations are associated with low-grade gliomas with increased survival and less commonly with glioblastoma. To the authors' knowledge, there has been only 1 other published report of a primary gliosarcoma carrying an isocitrate dehydrogenase mutation. This rare genetic-histological combination highlights potential differences between glioblastoma and gliosarcoma and may warrant additional study.
authors.affiliation: Case Western Reserve University School of Medicine, Cleveland.|Cleveland Clinic Lerner College of Medicine, Cleveland.
authors.forename: Jason K
authors.initials: JK
authors.lastname: Hsieh
authors.affiliation: The Ohio State University School of Medicine, Columbus.
authors.forename: Christopher S
authors.initials: CS
authors.lastname: Hong
authors.affiliation: Department of Neurological Surgery, University Hospitals-Case Medical Center, Cleveland.
authors.forename: Sunil
authors.initials: S
authors.lastname: Manjila
authors.affiliation: Department of Pathology, and.
authors.forename: Mark L
authors.initials: ML
authors.lastname: Cohen
authors.affiliation: Case Western Reserve University School of Medicine, Cleveland.|Case Comprehensive Cancer Center, Case Western Reserve University School of Medicine, Cleveland; and.|Departments of Radiation Oncology and.
authors.forename: Simon
authors.initials: S
authors.lastname: Lo
authors.affiliation: Case Western Reserve University School of Medicine, Cleveland.|Case Comprehensive Cancer Center, Case Western Reserve University School of Medicine, Cleveland; and.|Neurology, University Hospitals-Seidman Cancer Center, Cleveland, Ohio.
authors.forename: Lisa
authors.initials: L
authors.lastname: Rogers
authors.affiliation: Case Western Reserve University School of Medicine, Cleveland.|Department of Neurological Surgery, University Hospitals-Case Medical Center, Cleveland.|Case Comprehensive Cancer Center, Case Western Reserve University School of Medicine, Cleveland; and.
authors.forename: Andrew E
authors.initials: AE
authors.lastname: Sloan
mesh_terms: D000368:Aged; D001932:Brain Neoplasms / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D018316:Gliosarcoma / Q000235:genetics* / Q000473:pathology / Q000601:surgery; D006801:Humans; D007521:Isocitrate Dehydrogenase / Q000235:genetics*; D008297:Male; D009154:Mutation / Q000235:genetics*
chemical_list: D007521:Isocitrate Dehydrogenase; C543588:IDH1 protein, human
keywords: EGFR = epidermal growth factor receptor; GFAP = glial fibrillary acidic protein; IDH1 = isocitrate dehydrogenase-1; glioblastoma; gliosarcoma; isocitrate dehydrogenase; oncology