title: Malignant Glioma with Neuronal Marker Expression : A Clinicopathological Study of 18 Cases.
abstract: OBJECTIVE
  Malignant gliomas with neuronal marker expression (MGwNM) are rare and poorly characterized. Increasingly diverse types of MGwNM have been described and these reported cases underscore the dilemmas in the classification and diagnosis of those tumors. The aim of this study is to provide additional insights into MGwNM and present the clinicopathological features of 18 patients.
  
  
  METHODS
  We reviewed the medical records of 18 patients diagnosed as MGwNM at our institute between January 2006 and December 2012. Macroscopic total resection was performed in 11 patients (61%). We evaluated the methylation status of O(6)-methylguanine-DNA methyltransferase (MGMT) and expression of isocitrate dehydrogenase 1 (IDH-1) in all cases, and deletions of 1p and 19q in available cases.
  
  
  RESULTS
  The estimated median overall survival was 21.2 months. The median progression-free survival was 6.3 months. Six patients (33%) had MGMT methylation but IDH1 mutation was found in only one patient (6%). Gene analysis for 1p19q performed in nine patients revealed no deletion in six, 19q deletion only in two, and 1p deletion only in one. The extent of resection was significantly correlated with progression free survival on both univariate analysis and multivariate analysis (p=0.002 and p=0.013, respectively).
  
  
  CONCLUSIONS
  In this study, the overall survival of MGwNM was not superior to glioblastoma. The extent of resection has a significant prognostic impact on progression-free survival. Further studies of the prognostic factors related to chemo-radio therapy, similar to studies with glioblastoma, are mandatory to improve survival.
authors.affiliation: Department of Neurosurgery, Konyang University Hospital, Konyang University School of Medicine, Daejeon, Korea.
authors.forename: Hong Rye
authors.initials: HR
authors.lastname: Kim
authors.affiliation: Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jae Jun
authors.initials: JJ
authors.lastname: Lee
authors.affiliation: Department of Neurosurgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jung-Il
authors.initials: JI
authors.lastname: Lee
authors.affiliation: Department of Neurosurgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Do Hyun
authors.initials: DH
authors.lastname: Nam
authors.affiliation: Department of Pathology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Yeon-Lim
authors.initials: YL
authors.lastname: Suh
authors.affiliation: Department of Neurosurgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Ho Jun
authors.initials: HJ
authors.lastname: Seol
keywords: 1p and 19q; Expression of isocitrate dehydrogenase 1; Malignant gliomas; Methylation status of O6-methylguanine-DNA methyltransferase; Neuronal marker