Low-grade brain tumours and seizures
- Edinburgh Centre for Neuro-Oncology, Western General Hospital, Edinburgh, UK
- Correspondence to Simon Kerrigan, Edinburgh Centre for Neuro-oncology, Western General Hospital, Edinburgh EH4 2XU, UK;
- Received 18 November 2011
- Accepted 11 January 2012
Up to 80% of people with low-grade brain tumours (WHO Grade I and II) experience seizures at some time during their illness, compared with up to 60% of people with high-grade tumours (WHO Grade III and IV).1 For most patients with low-grade tumours, seizures are the presenting complaint and in approximately half of cases the seizures are refractory to medical treatment. We have used two cases to illustrate some dilemmas and difficulties arising from the management of low-grade brain tumours presenting with seizures.
Patient 1 suffered a generalised tonic-clonic seizure while driving. He attended the emergency room and had an unenhanced CT brain scan (figure 1). This showed a low density lesion in the right posterior frontal lobe. The lesion appeared to spare the grey matter but with a suspicion of vasogenic oedema and an underlying mass lesion; thus, contrast enhanced imaging was suggested.
MRI of the brain, with and without gadolinium contrast, confirmed the suspicion of an underlying mass lesion (figure 2). The absence of contrast enhancement was felt to be consistent with an underlying low-grade glioma. On further questioning, the patient described several previous episodes of transient left arm dysfunction and also a subtle change in personality over the preceding months. Neurological examination was completely normal.
What to do now?
This patient has had one clear seizure and several other episodes that may have been partial-onset seizures, and abnormal brain imaging suggesting a possible low-grade brain tumour. How would you manage this patient now?
To answer this question you need an idea of what is likely to happen if no intervention is carried out, that is, what is the natural history of low-grade brain tumours?
The natural history of low-grade brain tumours
Although survival from low-grade brain tumours is much better …