title: Ependymal tumors with oligodendroglioma like clear cells: Experience from a tertiary care hospital in Pakistan.
abstract: BACKGROUND
  Ependymal tumors with oligodendroglioma like clear cells have never been reported from Pakistan. We aimed to see the features and outcomes of this rare entity.
  
  
  METHODS
  It was retrospective cohort conducted at the Department of Neurosurgery, Aga Khan University from 2003 to 2013. The medical records and radiology of patients with proven histopathology were reviewed. Analysis was done on SPSS 20.
  
  
  RESULTS
  Eleven cases of ependymal tumors with clear cells were found, which equated to 1.5% of the total tumor burden in 11 years. The median age was 49 years. Most common presenting symptom was headache 54.5%. Out of 11 patients, 9 patients had a supratentorial tumor. Magnetic resonance imaging showed hypointense signals on T1 and hyperintense signals on T2-weighted images in all cases. Contrast enhancement was found in 9 patients (77.8%), necrosis and hemorrhage was found in 4 (36%) and 3 (27%) patients, respectively. Immunohistochemistry showed glial fibrillary acidic protein and epithelial membrane antigen positivity in all cases. Ki-67 showed high proliferative index in 6 patients. According to the World Health Organization grading of ependymal tumors, 2 patients had Grade II tumors, and 9 patients had Grade III tumors with clear cells. Gross total resection was achieved in 6 (54.5%) and subtotal resection in 5 patients (45.4%). Recurrence was observed in 9 patients. Six patients died of the disease. Median progression-free survival and overall survival was 8 months and 10 months, respectively.
  
  
  CONCLUSIONS
  Ependymal tumors with clear cells presented more commonly in Grade III lesions and were more aggressive in behavior with poorer outcome compared to similar studies.
authors.affiliation: Department of Surgery, Section of Neurosurgery, Aga Khan University, Karachi, Pakistan.
authors.forename: Fauzan Alam
authors.initials: FA
authors.lastname: Hashmi
authors.affiliation: Department of Surgery, Section of Neurosurgery, Aga Khan University, Karachi, Pakistan.
authors.forename: Muhammad Faheem
authors.initials: MF
authors.lastname: Khan
authors.affiliation: Department of Surgery, Section of Neurosurgery, Aga Khan University, Karachi, Pakistan.
authors.forename: Saad Akhtar
authors.initials: SA
authors.lastname: Khan
authors.affiliation: Department of Surgery, Section of Neurosurgery, Aga Khan University, Karachi, Pakistan.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Waqas
authors.affiliation: Department of Surgery, Section of Neurosurgery, Aga Khan University, Karachi, Pakistan.
authors.forename: Muhammad Ehsan
authors.initials: ME
authors.lastname: Bari
authors.affiliation: Department of Pathology, Section of Histopathology, Aga Khan University, Karachi, Pakistan.
authors.forename: Arsalan
authors.initials: A
authors.lastname: Ahmed
keywords: Anaplasia; clear cells; overall survival; progression-free survival; supratentorial