MICROSCOPIC DESCRIPTION: 1-5. Sections show fragments of a moderately hypercellular glioma with prominent background oedema. The tumour cells demonstrate variable morphology with specimens 1-3 showing moderate nuclear and cellular pleomorphism with rounded nuclei and perinuclear halos. Specimens 4-5 show increased tumour pleomorphism with scattered bizarre multinucleated tumour cells and frequent mitotic figures (up to 12 per 10hpf). There is prominent perivascular lymphocytic cuffing. No microvascular proliferation or palisaded tumour necrosis is seen. Immunohistochemistry results show tumour cells stain:
- GFAP Positive Nestin Positive (intermediate)
- NogoA Negative
- IDH-1 R132H Positive (mutated)
- ATRX Positive (not mutated)
- MGMT Negative (likely methylated)
- p53 Positive (favours astrocytoma)
- p16 CDKN2A Negative
- Topoisomerase labelling index: Approximately 40%.
DIAGNOSIS: 1&2. Brain tissue, frontal tumour: IDH-1 mutated/ATRX wild type anaplastic glioma (WHO grade III), favouring astrocytoma.
SUPPLEMENTARY REPORT FISH for chromosome 1p/19q deletion. 1p36 NO DELETION DETECTED.
Images and report courtesy of the Royal Melbourne Hospital Pathology Department.