- To discuss and illustrate the pattern of glioblastoma imaging abnormalities correlating to classification, histological and molecular aspects. - To describe through illustrative cases the scenarios to diagnose, including early onset glioblastoma, patterns of involvement and post-treatment aspects. - To highlight the differential diagnosis and the imaging red flags that support the glioblastoma suspicion.

Glioblastoma (GBM) is an extremely aggressive diffuse glial tumour commonly found in the supratentorial white matter (WM) of the cerebral hemispheres. It is the most common primary brain tumour in adults, accounting for 25% of all cases. GBMs are largely resistant to therapy, and have a poor prognosis. The WHO classification has dropped the term “multiforme” and thus it is more appropriated to refer to these tumours merely as glioblastomas. Although "multiforme" should not be used, this tumour presents multiple patterns of presentation and its...

Gliomas are central nervous system (CNS) neoplasms that affect both the brain and spinal cord. They comprise a clinically, histologically and genetically very heterogeneous brain tumour category.Seventy-five percent of all gliomas are astrocytomas and the most common subtype is the highest-hgrade one (glioblastoma), which are notable for their dismal overall 5-year survival of 5%. The classification for gliomas has changed over the past decade, driven by advances in molecular analyses of these tumours. The World Health Organization Classification, 2016 edition (WHO 2016) chapter on gliomas...

GBM are very common tumours and have multiple patterns of involvement (previously called “multiforme"). Radiologist must be aware of the different imaging scenarios to optimize imaging protocols to support early and accurate diagnosis, besides helping in the treatment and follow-up of the patients.

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