Outcome of adult patients with temporal lobe tumours and medically refractory focal epilepsy

Background. Tumours are a well-recognized cause of medically intractable epilepsies. Tumours represent the primary pathology in 10%-30% of patients undergoing surgical treatment for chronic epilepsy. This study examines the surgical and epileptological outcome of adults with temporal lobe tumoural epilepsy treated within a comprehensive epilepsy surgery programme. Methods. Between 1999 and 2004, 99 consecutive patients have been operated for intractable temporal lobe epilepsy (TLE). Among these, 14 adult patients exhibited temporal lobe neoplasms associated with TLE. Every patient underwent a comprehensive presurgical evaluation including video-EEG monitoring, MRI, interictal PET scan, ictal SPECT and neuropsychological testing. Surgical strategies were determined in an interdisciplinary seizure conference and tailored to the findings of the presurgical evaluation. All patients were available for follow up at regular intervals after 3, 6, 12 months and yearly thereafter. Epileptological outcome was classified according to Engel [10] and the ILAE (International League Against Epilepsy)/systems [33]. Findings. The surgical procedures performed were temporal lobe resection in 3 patients, extended lesionectomy in 4 and extended lesionectomy with resection of the temporomesial structures in 7. One patient with an astrocytoma grade III underwent a second and third operation for recurrent disease. Histological results: Astrocytoma 5 patients, ganglioglioma/gangliocytoma 5, oligodendroglioma 2, ependymoma 1 and dysembryoplastic neuroepithelial tumour (DNET) 1. Postoperative follow-up was performed after 12-74 months (mean 31). The outcome according to the Engel classification indicated class IA in 9 patients, class IC in 3, and 1 each in classes IIIA and IVA. Epileptological outcome according to the ILAE classification indicated class 1 (12 patients) and class 4 (2 patients). Surgical mortality was zero and mild permanent neurological deficits due to surgery were seen in 2 patients. Postoperatively 3 patients showed a homonymous quadrantanopia. Conclusions. Patients with drug resistant epilepsy and temporal lobe tumours should undergo evaluation in dedicated epilepsy surgery programmes.