SURGICAL-TREATMENT OF NEOPLASMS ASSOCIATED WITH MEDICALLY INTRACTABLEEPILEPSY

OBJECTIVE: Surgical treatment in patients with brain tumors and medica lly intractable epilepsy is aimed at the removal of the neoplasm and c omplete seizure control. However, an adequate surgical approach is sti ll controversial. This study was designed to analyze the factors for t he optimum surgical treatment of these patients. METHODS: The clinical , electrophysiological, operative, and histopathological data of 146 c onsecutive patients who underwent surgery between November 1987 and Ma y 1995 for intrinsic brain tumors and pharmacoresistant epilepsy were evaluated. RESULTS: The majority of the tumors were located in the tem poral lobe (n = 116) and involved the cortical gray matter. The most f requent tumors were gangliogliomas (n = 65), pilocytic astrocytomas (n = 21), and dysembryoplastic neuroepithelial tumors (n = 19). All but three tumors (98%) were of low histopathological grade (World Health O rganization Grades I or II). The biological behavior of the tumors was strikingly indolent, as indicated by a long preoperative history of c hronic seizures (mean, 14 yr). In all cases, complete resection of the tumor, including the epileptogenic area (as determined by noninvasive and/or invasive recordings of the zone of seizure onset and persisten t interictal activity), was intended. Complications were encountered i n 11 cases (8%). However, no patient died and there was no permanent m orbidity. Of the 124 patients who had postoperative follow-up examinat ions more than 6 months after resection, 71% were seizure-free, 11% ha d no more than two seizures per year, 13% showed a reduction of seizur e frequency of at least 75%, and 5% had no appreciable reduction in se izure frequency. CONCLUSION: The data indicate that neoplasms associat ed with medically intractable epilepsy constitute a distinct clinicopa thological group of tumors that arise in young hosts, involve the cort ex, and exhibit indolent biological behavior for many years. Complete surgical removal of these tumors, including the epileptogenic area, ca n achieve excellent seizure control.