Epilepsy in primary intracranial tumors in a neurosurgical hospital in Enugu, South-East Nigeria

Background: Seizures may be manifestation of intracranial tumor (IT) and demand thorough neurological evaluation. This paper examines epidemiology, lesion characteristics and outcome of seizures associated with primary IT. Methods: Retrospective analysis of medical records, computed tomography and magnetic resonance imaging of patients diagnosed with IT who presented with seizure from 2003 to 2013 at Memfys Hospital for Neurosurgery Enugu. Postoperative seizure outcome was based on Engel classification and correlated with tumor histology, patient age, anatomical location, time of presentation and extent of tumor resection. Data were analyzed using descriptive and inferential statistics. Results: Sixty-two patients (34.6%) presenting with seizures were analyzed. Peak age at presentation was in 6 (th) decade. Age of seizure onset had bimodal peak at 4 (th) and 6 (th) decades. Apart from IT located in posterior fossa with mortality of 62.5%, postoperative mortality did not depend on anatomical location of tumor. Postoperative seizure outcome and mortality depend on tumor histology (P = 0.025) and preoperative seizure duration (P = 0.036). Seizure duration shorter than 1 month had poor postoperative seizure outcome and high mortality. Although more patients with meningioma experienced seizures compared to glioma (P = 0.025), there was no difference in proportion of patients with meningioma and glioma who presented with seizure (P = 1.00). Extent of resection predicts postoperative seizure outcome based on meningioma sub-group analysis. Overall, 59.7% of patients had good postoperative seizure outcome, 21.0% had poor outcome and 19.3% died. Conclusion: Seizures of short duration, IT located in posterior fossa and gliomas are associated with poor postoperative seizure outcome and high patient mortality. Tumor histology does not seem to affect seizure predisposition. Most seizures associated with IT occur in fifth and sixth decades of life and affect frontal lobe most often.