Glioblastoma IDH wild-type

Heterogeneously enhancing right temporal mass with surrounding edema. 

A heterogenous right temporal lobe mass with thick irregular enhancing margins and central non-enhancement is noted. Surrounding high flair/T2 signal consistent with vasogenic edema. Susceptibility artefact centrally is consistent with blood product. Compression of the right midbrain and right lateral ventricle with entrapment and dilatation of the left lateral ventricle. 3mm midline shift to the left and effacement of the overlying sulci. The right MCA is displaced anteriorly.

MR perfusion demonstrates elevation of cerebral blood volume. MR spectroscopy demonstrates reduced NAA and elevated lactate. Choline is elevated in the peri-tumoral white matter. 

Conclusion:

1. Findings are consistent with a high grade glioma (GBM) in the right temporal lobe
2. Incidental pineal lesion has a solid enhancing component, larger than normal pineal tissue and thus is suspicious for a pineal tumor, most likely a pineocytoma.

The patient went on to have surgery.

Histology

MICROSCOPIC DESCRIPTION: Sections show fragments of a moderately hypercellular astrocytic glioma. Tumor 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 tumor necrosis are also identified.

Immunohistochemistry results show tumor cells stain:

• GFAP Positive (moderate)
• Nestin Positive (high)
• NogoA Negative
• IDH-1 R132H Negative (not mutated)
• ATRX Positive (not mutated)
• MGMT Positive (likely non-methylated)
• p53 Positive
• p16 CDKN2A Negative
• Topoisomerase labeling index: Approximately 30%.

FINAL DIAGNOSIS: IDH-1 wild type glioblastoma (WHO Grade IV).