WHO grade IV


formerly glioblastoma multiforme, GBM


Suggested by MRI and confirmed by pathology (brain biopsy/resection)

Findings on Investigations:


  • Cerebral hemispheres, corpus callusum. Rarely brainstem, spinal cord
  • Large, irregular, ring enhancing or irregular enhancing. ‘butterfly pattern’ if it spreads via the corpus callosum. Oedema.
  • T1: low signal
  • MRI T2,FLAIR: high signal vasogenic oedema


Histology: marked nuclear atypia, mitosis, microvascular proliferation, +/-necrosis. Also, pseudopalisading of cells around necrosis, some have giant cells
Tumor genetics:

  • Primary GBM: EGFR chr. 7p12 overexpression, PTEN (MMAC1) mutation, CDKN2A chr. 9p21(p16=INK4a) deletion. Occasionally MDM2 amplification
  • Secondary GBM: p53 17p13.1mutation,


Radiation therapy:

  • Fractionated focal irradiation in daily fractions of 2 Gy 5 days/week X 6 weeks, for a total of 60 Gy.
  • Or focal radiation in daily fractions of 1.8 Gy given 5 days per week, for a total dose of 50 Gy.

Consider chemotherapy:

  • Temozolamide TMZ.
  • Bevacizumab after extensive surgery, radiotherpy & temozolamide

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