Seizure characteristics and their treatment in pediatric brain tumour patients: A proposal for a service evaluation criteria

Objective: We aimed to describe the incidence of epileptic seizures in children with brain tumours, risk factors related, the seizure treatments used, the withdrawal of antiepileptic drugs (AEDs). Methods: Case note review of 120 newly diagnosed brain tumour patients referred between 01/2010 and 12/2014 to the regional paediatric cancer service was carried out to determine patient tumour and seizure characteristics, AED treatments and outcomes. Results: We excluded 2 patients because of previous long history of seizure in tuberous sclerosis and 1 patient has been lost in follow up. 67/117 were male (57,3%), median age at tumour presentation was 8.1 years (IQR 25e75: 3.6e12.7). The median follow up was 33 months (IQR 25e75: 24e56). 29,2% experienced seizures. Risk factors for seizures were cerebral localisation in logistic regression analysis (OR: 7,07 IC 95% 2,89e17,3). In particular, neither age at diagnosis nor tumour type were associated with seizure risk. The epilepsy follow up at a median of 24 months (IQR 25e75: 15e48) demonstrated that 37,1% were seizure free (SF) off AEDs, 42,9% were SF on AEDs and 20% experienced refractory epilepsy. The most of them had a single seizure episode (62,9%). 12 patients withdraw AED. The median duration of AED before withdrawal was 11 months (IQR 25e75: 5e14 months), and the median follow up after withdrawal was 15 months (IQR 25e75: 5e34 months). 4 children had seizure relapse after further acute events (2 had acute hydrocephalus, 1 had sepsis, 1 had ventriculitis after shunt revision). Only 1 patient did not have AED at diagnosis of epilepsy. Conclusion: Epileptic seizures affect about 1/3rd of children presenting with brain tumours, most commonly in cortically-located tumours. The low risk of recurrent seizures after treatment justifies early withdrawal of AED after seizures stabilisation. A 3 month seizure free interval prior to AED withdrawal is proposed for future studies.