This case illustrates the difficulty conventional imaging has in distinguishing a low-grade tumour with indolent biological behaviour from early imaging of a more aggressive tumour. In this case were a biopsy to have been performed at the time of the first scan it would almost certainly have demonstrated a diffuse low-grade glioma. At that stage, however, it would have been IDH negative, which would have been predictive of aggressive behaviour.
Although the very aggressive behaviour is entirely consistent with IDH wild-type molecular subtype, as is MGMT being unmethylated 1, to conclusively establish this IDH would need to be sequenced to ensure that a non-IDH1 R132H mutation was present. This is particularly relevant in young patients.