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
- Primary GBM: EGFR chr. 7p12 overexpression, PTEN (MMAC1) mutation, CDKN2A chr. 9p21(p16=INK4a) deletion. Occasionally MDM2 amplification
- Secondary GBM: p53 17p13.1mutation,
- 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.
- Temozolamide TMZ.
- Bevacizumab after extensive surgery, radiotherpy & temozolamide