title: Glioblastoma multiforme of the optic chiasm: A rare case of common pathology.
abstract: BACKGROUND
  Malignant optic and chiasmatic gliomas are extremely rare, and are classified pathologically as anaplastic astrocytoma or glioblastoma multiforme (GBM). Approximately 40 cases of optic GBM in adults have been reported in the literature, and only five of them were described to originate from the optic chiasm.
  
  
  METHODS
  An 82-year-old male patient with a past medical history of diabetes mellitus type 2, melanoma, and bladder cancer presented with gradual vision loss of the left eye in a period of 1 month. After neuro-ophthalmological examination, the decision of thither magnetic resonance imaging (MRI) studies was made. It showed a contrast enhancing mass in the region of the optic chiasm. In this case, imaging study was not enough to establish an accurate diagnosis and a left pterional craniotomy for biopsy and resection of the optic chiasmal mass was performed. After histological evaluation of the mass tissue, the diagnosis of GBM was made. Taking into account the patient's poor condition and unfavorable prognosis he was moved to inpatient hospice. The patient deceased within 2 months after surgery.
  
  
  CONCLUSIONS
  Chiasmal GBM is an extremely rare condition where a biopsy is necessary for accurate diagnosis and optimal treatment. Differential diagnosis for such lesions can be very difficult and include demyelinating optic neuritis and non-demyelinating inflammatory optic neuropathy (e.g., sarcoid), vascular lesions (e.g., cavernoma), compressive lesions of the optic apparatus, metastatic malignancy, and primary tumors of the anterior optic pathway. The role of chemotherapy and radiotherapy including novel stereotaxic radiosurgery methods is still unclear and will need to be evaluated.
authors: Department of Pathology and Laboratory Medicine, Miller School of Medicine, University of Miami, Miami, FL, USA.
authors: Kirill A
authors: KA
authors: Lyapichev
authors: Department of Neurosurgery, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, USA.
authors: Amade
authors: A
authors: Bregy
authors: Department of Neurological Surgery, Miller School of Medicine, University of Miami, Miami, Florida, USA.
authors: Adrienne
authors: A
authors: Cassel
authors: Department of Neurological Surgery, Miller School of Medicine, University of Miami, Miami, Florida, USA.
authors: Chelsea
authors: C
authors: Handfield
authors: Department of Pathology and Laboratory Medicine, Miller School of Medicine, University of Miami, Miami, FL, USA.
authors: Jose
authors: J
authors: Velazquez-Vega
authors: Aventura, Florida, USA.
authors: Matthew D
authors: MD
authors: Kay
authors: Department of Neurological Surgery, Miller School of Medicine, University of Miami, Miami, Florida, USA.
authors: Gregory
authors: G
authors: Basil
authors: Department of Neurological Surgery, Miller School of Medicine, University of Miami, Miami, Florida, USA.
authors: Ricardo J
authors: RJ
authors: Komotar
keywords: Brain tumor; glioblastoma; glioma