Glioblastoma IDH wild-type (dural tail)
Visual field loss.
Loading Stack -
0 images remaining
A large heterogeneously enhancing tumour on the inferior surface of the temporal lobe is noted. It appears intra-axial but does abutt the dura and on coronal imaging demonstrates a dural tail.
Overall appearances suggest a high grade glioma, e.g. glioblastoma.
Patient went on to have surgery
MICROSCOPIC DESCRIPTION: Paraffin sections show fragments of a densely hypercellular glial tumour. Tumour cells have fibrillary astrocytic morphological features with moderate nuclear pleomorphism. Scattered mitotic figures are identified. There are foci of microvascular proliferation with multilayering of atypical cells around vessel lumena. Additionally, an area of confluent necrosis is identified. This incorporates thin-walled necrotic blood vessels.
- GFAP positive.
- Nestin positive (high).
- IDH-1 R132H negative (not mutated).
- ATRX negative (mutated).
- MGMT negative (likely methylated).
- p53 positive.
- p16 CDKN2A negative.
- Topisomerase labelling index: Approximately 25%.
FINAL DIAGNOSIS: IDH-1 wild type, ATRX mutated glioblastoma (WHO Grade IV).
Dural tails are often felt to be nearly pathognomonic of a meningioma, which is simply not true; it is not infrequently seen in intra-axial tumours too.
Although this is tumour is entirely consistent with an IDH wild-type glioblastoma, to conclusively establish that this is, in fact, the case IDH would need to be sequenced to ensure that a non-IDH1 R132H mutation was absent.