Pathology
H&E
Topoisomerase
IDH-1
The patient went on to have surgery.
Histology
MICROSCOPIC DESCRIPTION: Paraffin sections show fragments of a moderately hypercellular glial tumour involving cortex and white matter. Tumour cells have predominantly fibrillary astrocytic morphology with moderate nuclear and cellular pleomorphism. An occasional mitotic figure is identified. There is no microvascular proliferation and no necrosis is identified. A background population of morphologically unremarkable neurones is noted. No bi-nucleate forms are identified.
IMMUNOHISTOCHEMISTRY:
- GFAP positive
- Nestin negative
- Nogo A positive in native oligodendrocytes
- IDH-1 R132H negative (not mutated)
- ATRX positive (not mutated)
- MGMT negative (likely methylated)
- p53 negative p16 CDKN2A positive
- Topoisomerase labelling index: Approximately 5%.
FINAL DIAGNOSIS: IDH-1 R132H wild type diffuse astrocytoma (WHO Grade II).