Nonconvulsive status epilepticus in metastatic CNS disease

Convulsive seizures are common, easily recognized manifestations of primary or metastatic brain tumors that affect approximately 50% of patients. (1) Nonconvulsive status epilepticus (NCSE) is often a more challenging diagnosis because clinical features may include altered mental status in the absence of convulsive activity. NCSE was found in 6% of patients with systemic cancer presenting with altered mental status who had no evidence of CNS metastasis. (2) NCSE has also been reported in patients with primary brain tumors. (3,4) We describe the clinical and diagnostic characteristics of four patients with metastatic CNS disease presenting in de novo NCSE and report treatment outcomes.