MICROSCOPIC DESCRIPTION: Sections show fragments of a moderately hypercellular astrocytic glioma. Tumour cells show moderate nuclear and cellular pleomorphism. Scattered mitotic figures are identified. There is prominent microvascular proliferation with multilayering of atypical cells around vessel lumena. Areas of palisaded tumour necrosis are also identified.
Immunohistochemistry results show tumour cells stain:
- GFAP Positive
- Nestin Positive (high)
- IDH-1 R132H Negative (not mutated)
- ATRX Positive (not mutated)
- MGMT Negative (likely methylated)
- p53 Positive
- p16 CDKN2A Negative
Topoisomerase labelling index: Approximately 30%.
DIAGNOSIS: IDH-1 wild type Glioblastoma (WHO Grade IV).