GBM

Occurs in adults 

- Mean survival ~1 year (vs 3 years for AA, 6-8 years for grade II astrocytoma) 

- Can occur spontaneously as a primary tumor (EGFR, PTEN, p16) 

- Can evolve from grade II/III tumors (p53, IDH-1/IDH-2) IDH changes methylation of genes, changes expression 

Subtypes: 

(source: sturm et al 2012, cancer cell) 

- may arise from specific subtypes of cells? 

Path: 

- palisading cells around central areas of necrosis 

- endovascular cell proliferation - plump endovascular cells proliferating out of proportion - almost appear like glomeruli 

- giant cell variant 

Imaging: 

- heterogenous appearing 

- usually contrast-enhancing, sometimes ring-enhancing 

- can be bilateral or multifocal 

- butterfly GBM

- multifocal GBM