Longitudinal mutational analysis of a cerebellar pilocytic astrocytoma recurring as a ganglioglioma

Pediatr Blood Cancer. 2017 Feb;64(2):275-278. doi: 10.1002/pbc.26215. Epub 2016 Oct 8.

Abstract

A cerebellar pilocytic astrocytoma (PA) in a child recurred first with a PA histology and then with features of a ganglioglioma (GG). Molecular genetic analyses of the tumors confirmed a BRAF V600E mutation in all. They also all harbored a T202M mutation in ERK1, a kinase downstream of BRAF that is implicated in glial versus neuronal differentiation. The GG sample contained several variants that were not present in the PA samples; in particular, it had a truncating mutation in MAP2. These findings not only underscore the role of BRAF as oncogenic driver but also suggest that other genes may influence tumor morphology.

Keywords: BRAF V600E mutation; ganglioglioma; pilocytic astrocyoma; whole-exome sequencing.

Publication types

  • Case Reports
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Astrocytoma / complications
  • Astrocytoma / genetics*
  • Astrocytoma / pathology
  • Biomarkers, Tumor / genetics*
  • Brain Neoplasms / etiology*
  • Brain Neoplasms / pathology
  • Cerebellar Neoplasms / complications
  • Cerebellar Neoplasms / genetics*
  • Cerebellar Neoplasms / pathology
  • Child, Preschool
  • DNA Mutational Analysis
  • Female
  • Ganglioglioma / etiology*
  • Ganglioglioma / pathology
  • Humans
  • Mutation / genetics*
  • Neoplasm Recurrence, Local
  • Prognosis
  • Proto-Oncogene Proteins B-raf / genetics*

Substances

  • Biomarkers, Tumor
  • BRAF protein, human
  • Proto-Oncogene Proteins B-raf

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