Malignant gliomas with primitive neuroectodermal tumor-like components: A clinicopathologic and genetic study of 53 cases

Academic Article


  • Central nervous system neoplasms with combined features of malignant glioma and primitive neuroectodermal tumor (MG-PNET) are rare, poorly characterized, and pose diagnostic as well as treatment dilemmas. We studied 53 MG-PNETs in patients from 12 to 80 years of age (median = 54 years). The PNET-like component consisted of sharply demarcated hypercellular nodules with evidence of neuronal differentiation. Anaplasia, as seen in medulloblastomas, was noted in 70%. Within the primitive element, N-myc or c-myc gene amplifications were seen in 43%. In contrast, glioma-associated alterations involved both components, 10q loss (50%) being most common. Therapy included radiation (78%), temozolomide (63%) and platinum-based chemotherapy (31%). Cerebrospinal fluid (CSF) dissemination developed in eight patients, with response to PNET-like therapy occurring in at least three. At last follow-up, 27 patients died, their median survival being 9.1 months. We conclude that the primitive component of the MG-PNET: (i) arises within a pre-existing MG, most often a secondary glioblastoma; (ii) may represent a metaplastic process or expansion of a tumor stem/progenitor cell clone; (iii) often shows histologic anaplasia and N-myc (or c-myc) amplification; (iv) has the capacity to seed the CSF; and (v) may respond to platinum-based chemotherapy regimens. © 2008 The Authors.
  • Authors

    Published In

  • Brain Pathology  Journal
  • Digital Object Identifier (doi)

    Author List

  • Perry A; Miller CR; Gujrati M; Scheithauer BW; Zambrano SC; Jost SC; Raghavan R; Qian J; Cochran EJ; Huse JT
  • Start Page

  • 81
  • End Page

  • 90
  • Volume

  • 19
  • Issue

  • 1