What features make this tumour most likely to be a high grade glioma?
The tumour has a heterogeneous aspect with cystic component, susceptibility artefact (blood/calcification) and enhancement.
Fiducial markers identified at bifrontal regions.
A large cortical-based mass is present within the right parietal lobe, involving the right postcentral and superior parietal gyri. The mass has ill defined margin. It is predominantly solid and demonstrates multiloculated cystic component in its medial aspect in the parafalcine region. Mass also demonstrates susceptibility artefacts indicating the presence of either calcification or blood products. Minimal patchy enhancement is noted after contrast administration.
Despite its large size, the mass incites minimal vasogenic oedema. Positive mass effect is exerted onto the adjacent right lateral ventricle but no midline shift is noted. The postero-medial margin of the mass is close to the superior sagittal sinus, the sinus however still maintains its normal flow void and does not appear to be encased or compressed by the mass.
The rest of the brain is unremarkable.
Conclusion: Large cortical based mass within right parietal lobe with involvement of the right postcentral gyrus. Appearance is in keeping with a neoplastic lesion, primary tumour favoured over secondary. It is likely to be at least anaplastic astrocytoma and probably glioblastoma multiforme.