Resident Medical University Innsbruck, Department of Neurosurgery
Introduction: Higher age is a significant predictor for poor outcome in GBM patients. The impact of epilepsy in GBM patients is poorly defined. Furthermore, persisting epilepsy influences the patients’ quality of life (QoL). This study aims at specifically evaluating the impact of epilepsy in elderly GBM patients.
Methods: Two Austrian academic centers retrospectively analyzed all elderly (≥65 years) GBM patients with de-novo-tumors, who underwent first surgery between 09/2006 and 07/2021. Epidemiological, histopathological and survival data were gained from patients’ electronic charts. Tumor volume was assessed using standardized software.
Results: 391 patients (55%males, 45%females) with a median age of 73 years (IqR) 68.5-77.5) were analyzed. The mean OS was 12.4 months (CI95% 10.9-14.0). Median preoperative Modified Rankin Scale (mRS) was 2 (IqR 1-3). Median tumor volume amounted to 26.47cm3 (IqR 12.65-43.49).
95/391 patients (24%) suffered from preoperative epilepsy. 17 patients still suffered from epilepsy after tumor resection. Eight patients developed new postoperative seizures, four patients showed a worsening of already preoperative seizures. Patients with lower tumor volumes experienced significantly more often seizures compared to patients with larger tumors, p< 0.001. Logistic regression showed patients with seizures had significantly lower mRS (p=0.032) and less frequently occipital tumor location (p=0.018). Moreover, they showed a significantly increased risk for postoperative aphasia (p=0.002). Postoperative epilepsy resulted in significantly prolonged hospitalization after surgery (p=0.009).
Survival did not correlate with preoperative epilepsy (p>0.05). However, Cox regression revealed that multifocal tumor location (HR=1.777, p=0.025) as well as thalamic involvement (HR=11.121, p=0.030) negatively influenced OS. Furthermore, surgery-associated complications shortened OS significantly (HR=1.945, p=0.025).
Conclusion : Even though epilepsy did not directly impact survival in elderly GBM patients, surgery and AED led to epilepsy freedom in a significant proportion of our patient cohort, thereby potentially leading to improved QoL. Greatest focus should be set on avoiding any surgery-associated deficits, since these severely influence the OS.
