Long-term outcome and risk factors for uncontrolled seizures after a first seizure in children with hematological malignancies.

Long-term outcomes of seizures that develop during treatment of childhood hematological malignancies have not been described. We analyzed seizure outcome in 62 children with leukemia or lymphoma treated at our institution. There was a median follow-up of 6.5 years since first seizure. Seizure etiology included intrathecal or systemic methotrexate in 24, leucoencephalopathy in 11, brain hemorrhage or thrombosis in 11, meningitis in 4, and no identifiable cause in 12. Seizures remained uncontrolled in 18, and risk factors for poor control included female sex (P = .02), no seizure control with first antiseizure drug (P = .08), and longer interval between cancer diagnosis and seizure onset (P = .09). Poor seizure control after initial antiseizure drug also predicted recurrent seizure after drug withdrawal (P = .04). In conclusion, seizures are controlled with medications in a majority of patients with hematological cancer. After a period without seizures, antiseizure drug withdrawal in appropriately selected patient has a high success rate.