Seizure characteristics are related to tumor pathology in children with brain tumors

Brain tumors are found in 1-3% of children with newly onset of seizures. Understanding the impact of seizures on pediatric brain tumors and factors between seizures and brain tumors are crucial. This study aimed to evaluate the association of pediatric brain tumors on seizure occurrence and the relationships between seizures and the diagnosis and prognosis of brain tumors.

In a cohort of 184 children with newly diagnosed brain tumors between August 2012 and September 2017, 56 patients with brain tumor-associated seizures were evaluated for their clinical characteristics, electroencephalography (EEG), tumor pathology, response to anti-epileptic drugs (AEDs) and their seizure outcome.

The prevalence of seizures in our cohort of children with brain tumors was 30.4% (n = 56/184). Supratentorial tumors were more commonly associated with seizures than were infratentorial tumors (89.3% vs. 10.7%; P <  0.01). Among patients with tumor-associated seizures, the tumors were most commonly located in the temporal lobe (32.1%), followed by the frontal (21.4%) and parietal lobes (16.1%) and other cortices. Thirty-four patients (60.7%) had benign tumor pathology and 22 patients (39.3%) had malignant tumor pathology; low grade astrocytoma (n = 15; 26.8%) was the most common histology type. Seizure onset at initial presentation was more frequently observed in the patients with benign tumors, whereas the patients with malignant tumors tended to have delayed seizure onset (P < 0.01). On EEGs, focal epileptiform discharges were more commonly seen in benign tumors, whereas focal and diffuse slow waves were most commonly associated with malignant tumors. Levetiracetam was the most commonly prescribed AED to treat brain-tumor-associated seizures.

In children with brain tumors, higher seizure frequency with normal neurologic examination was more prevalent in benign tumors, whereas less frequent seizures with focal weakness and signs of increased intracranial pressure were more indicative of malignancy. Delayed onset of seizures was more often observed in the children with malignant brain tumors. Seizure characteristics play an important role in relation to tumor biology and epileptogenesis in pediatric brain tumors.