MICROSCOPIC DESCRIPTION: Paraffin sections show fragments of a densely hypercellular astrocytic glioma. Tumour cells show marked nuclear and cellular pleomorphism. Frequent mitotic figures are identified and there is prominent microvascular proliferation. Foci of palisaded necrosis are also noted. The features are of glioblastoma (WHO Grade IV). Neither oligodendroglioma or PNET components are identified.
IMMUNOHISTOCHEMISTRY:
- GFAP: positive
- Nestin: positive
- IDH-1 R132H: positive (mutated)
- MGMT: negative (likely methylated)
- p53: positive
- p16: positive T
- topoisomerase labelling index: approximately 30%
FINAL AGNOSIS: secondary glioblastoma (WHO Grade IV)