Abstracts

Rationale: The objectives were to determine the incidence, clinical presentation, electrographic correlates, prognostic factors and outcome of (NCSE) in cancer patients at Memorial Sloan-Kettering Cancer Center (MSKCC). Methods: We reviewed 711 electroencephalography (EEG) reports in 549 patients done at MSKCC from July 1, 2006 to December 31, 2007 to identify cases of NCSE. We reviewed medical records to identify patients with NCSE, the causes of NCSE, response to treatment and patient outcome. We collected information on the patient’s history of prior seizures, antiepileptic drugs (AED) and AED levels. Using the Epilepsy Research Foundation 1 criteria for NCSE, we classified the patients as either definite or probable NCSE. Available neuroimaging studies were reviewed to assess new or worsening structural disease of the brain. EEGs of patients with NCSE were re-reviewed. We evaluated response of NCSE to treatment and determined mortality from the time of NCSE diagnosis. Results: Twenty-one patients (4%) were identified as having NCSE. Eleven had primary brain tumors, 8 had CNS metastasis, and 2 had no structural brain disease. At presentation, 4 patients were stuporous or comatose, 2 were lethargic, and 15 were awake or drowsy during the EEG recording but were intermittently confused. Fourteen of the 21 patients had at least one convulsive seizure prior to the NCSE episode; all had an intracranial tumor. Seven patients presented with NCSE without prior seizures. Review of labs did not reveal significant changes in electrolyte levels and only one patient had a sub-therapeutic level of an AED (phenytoin). Neuroimaging revealed new CNS pathology in 67% of patients with NCSE. EEG findings included a recorded seizure in 71% of studies performed. Also seen were Periodic Lateralized Epileptiform Discharges (PLEDs) (33%) and Periodic Epileptiform Discharges (PED) (24%). Fifteen (71%) patients died within one month NCSE. NCSE was controlled in 100% of patients, but outcome was poor due to underlying disease. Conclusions: NCSE is a treatable condition in cancer patients despite the high prevalence of structural brain disease. It usually presents as a change in mental status, and EEG affords easy diagnosis. 1. Walker M, Cross H, Smith S, Young C, Aicardi J, Appleton R, Aylett S, et al. Nonconvulsive status epilepticus: Epilepsy Research Foundation Workshop Reports. Epileptic Disorder 2005;7:253-96.