Polymorphous low-grade neuroepithelial tumor of the young (PLNTY): an epileptogenic neoplasm with oligodendroglioma-like components, aberrant CD34 expression, and genetic alterations involving the MAP kinase pathway

Acta Neuropathol. 2017 Mar;133(3):417-429. doi: 10.1007/s00401-016-1639-9. Epub 2016 Nov 3.


Epileptogenic tumors affecting children and young adults are a morphologically diverse collection of neuroepithelial neoplasms that, as a group, exhibit varying levels of glial and/or neuronal differentiation. Recent advances in molecular profiling technology, including comprehensive DNA sequencing and methylation analysis, have enabled the application of more precise and biologically relevant classification schemes to these tumors. In this report, we describe a morphologically and molecularly distinct epileptogenic neoplasm, the polymorphous low-grade neuroepithelial tumor of the young (PLNTY), which likely accounts for a sizable portion of oligodendroglioma-like tumors affecting the pediatric population. Characteristic microscopic findings most notably include infiltrative growth, the invariable presence of oligodendroglioma-like cellular components, and intense immunolabeling for cluster of differentiation 34 (CD34). Moreover, integrative molecular profiling reveals a distinct DNA methylation signature for PLNTYs, along with frequent genetic abnormalities involving either B-Raf proto-oncogene (BRAF) or fibroblast growth factor receptors 2 and 3 (FGFR2, FGFR3). These findings suggest that PLNTY represents a distinct biological entity within the larger spectrum of pediatric, low-grade neuroepithelial tumors.

Keywords: BRAF; Epilepsy; FGFR2; FGFR3; Low-grade neuroepithelial tumor; Oligodendroglioma.

MeSH terms

  • Adolescent
  • Adult
  • Antigens, CD34 / genetics
  • Antigens, CD34 / metabolism*
  • Brain Neoplasms / complications*
  • Brain Neoplasms / diagnostic imaging
  • Brain Neoplasms / genetics*
  • Child
  • Child, Preschool
  • Epilepsy / etiology*
  • Epilepsy / genetics
  • Female
  • Gene Expression Regulation, Neoplastic / genetics*
  • Glial Fibrillary Acidic Protein / metabolism
  • Humans
  • Male
  • Mitogen-Activated Protein Kinases / genetics
  • Mitogen-Activated Protein Kinases / metabolism
  • Mutation*
  • Neoplasms, Neuroepithelial / complications*
  • Neoplasms, Neuroepithelial / diagnostic imaging
  • Neoplasms, Neuroepithelial / genetics
  • Neuroglia / pathology
  • Oligodendroglioma / genetics
  • Proto-Oncogene Mas
  • Proto-Oncogene Proteins B-raf / genetics
  • Receptors, Fibroblast Growth Factor / genetics
  • Signal Transduction / physiology*
  • Young Adult


  • Antigens, CD34
  • Glial Fibrillary Acidic Protein
  • MAS1 protein, human
  • Proto-Oncogene Mas
  • Receptors, Fibroblast Growth Factor
  • BRAF protein, human
  • Proto-Oncogene Proteins B-raf
  • Mitogen-Activated Protein Kinases