MICROSCOPIC DESCRIPTION: 1&2. Paraffin sections show fragments of a densely hypercellular astrocytic glioma. Tumour cells show moderate nuclear and cellular pleomorphism. Scattered mitotic figures are identified. There are foci of microvascular proliferation with multilayering of atypical cells around vessel lumena. In addition there are several foci of tumour necrosis incorporating thin-walled thrombosed blood vessels. The features are of glioblastoma multiforme (WHO Grade IV). Separate fragments of brain parenchyma uninvolved by tumour show reactive changes.
DIAGNOSIS: 1&2. Brain tissue: Glioblastoma.