Neuroradiology Board Review – Brain Tumors – Case 1
Neuroradiology brain tumor board review. This lecture is geared towards the ABR core exam for residents, but it would be useful for review for the ABR certifying exam or certificate of added qualification (CAQ) exam for neuroradiology.
More description and the answer (spoiler!) are seen below the video.
This case shows an MRI of the brain with a highly heterogeneous, expansile mass in the right frontal lobe extending into the corpus callosum. There is a large degree of mass effect. On postcontrast imaging, there is a rim of avid enhancement with central necrosis.
The diagnosis is: glioblastoma
Glioblastomas, or GBMs, are high grade primary glial tumors and the most common primary brain tumor. The definition has recently been changed to only include IDH-wild type tumors, with IDH-mutated tumors now called grade 4 astrocytomas. These tumors have a very poor prognosis despite maximal therapy. They are characterized by avidly enhancing, necrotic masses with surrounding T2 hyperintensity that is a mix of tumor and edema.
Molecular markers are increasingly important in determining the prognosis of brain tumors. IDH-mutated tumors have a better prognosis, as do tumors with MGMT methylation. 1p19q codeletion is the characteristic mutation associated with oligodendrogliomas. These facts are fair game on ABR exams.