[Incidence of brain tumors in cases of chronic epilepsy treated surgically]

An incidence of tumors of the brain as a cause of drug-resistant epilepsy have been analysed. The analysis included patients operated for epilepsy at the Department of Neurosurgery, Medical Academy in Warsaw between 1987 and 1991. Malignant tumors were found in 21 out 85 patients (24.7%) treated surgically, 22.4% were benign tumors, and 52.9%--lesions of cicatricial character. The most frequent malignant tumor was fibrillary astrocytoma, noted in 57.1% of cases. Neurological examination has revealed discrete symptoms only in 2 out of 21 patients. CT scans have showed non-characteristic focus of decreased density in 12 patients (57.1%). Differentiation of tumor-produced epilepsy and those due to other focal lesions could not be made with the clinical course of seizures and EEG records. Actually, an incidence of tumors of the brain causing seizures refractory to pharmacologic treatment is increasing. Not characteristic clinical course and EEG records as well as CT scans are the main causes of delays in the surgery.