QOL-13. THE ROLE OF EPILEPSY IN ELDERLY PATIENTS WITH GLIOBLASTOMA: AN AUSTRIAN MULTICENTER ANALYSIS

BACKGROUND

With an aging population, acquisition of a better understanding of prognostic factors in elderly patients with Glioblastoma multiforme (GBM) is of utmost importance. Epileptic seizures have been found to correlate with improved overall survival (OS) in low-grade gliomas; however, the impact of epilepsy in GBM patients on outcome parameters is poorly defined. This study aims at specifically evaluating the impact of epilepsy in elderly GBM patients. Material &

METHODS

Two Austrian academic neurosurgical centers retrospectively analyzed all elderly (≥ 65 years) GBM patients with de-novo tumors, who underwent surgery between 09/2006 and 07/2021. Epidemiological, histopathological and survival data were gained from patients’ electronic charts and screened for presence of epilepsy preoperatively or during follow-up. Tumor volume was assessed using standardized software.

RESULTS

391 patients (55% males, 45% females) with a median age at surgery of 73 years (IqR 68.5-77.5) were analyzed. The mean predicted OS was 12.4 months (CI95% 10.9-14.0). Mean follow-up was 10.4 months (CI95% 9.1-11.6) in our cohort. Median tumor volume amounted to 26.47 cm3 (IqR 12.65-43.49). 95 patients (24%) suffered from preoperative epilepsy. 17 (18%) patients showed epilepsy after tumor resection. Four patients (1.0%) showed a worsening of already preoperatively diagnosed seizures. Patients with lower tumor volumes experienced significantly more often seizures compared to patients with larger tumors, p< 0.001. Survival did not correlate with preoperative epilepsy (p > 0.05). However, Cox-regression revealed that multifocal tumor location (HR=1.777, p=0.025) and thalamic involvement (HR=11.121, p=0.030) influenced OS. Surgery-associated complications shortened OS significantly (HR=1.945 [CI95% 1,296-2,916], p=0.025).

CONCLUSION

Even though epilepsy was not found to directly impact survival in elderly GBM patients, we found that surgery 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.

OS02.7.A The role of epilepsy in elderly patients with Glioblastoma: An Austrian multicenter analysis

Background

Higher age is a significant predictor of poor outcome in glioblastoma multiforme (GBM) patients. Thus, acquisition of a better understanding of additional prognostic factors in these often-frail patients is of utmost importance. Epileptic seizures correlate with improved overall survival (OS) in low-grade gliomas; however, the impact of epilepsy in GBM patients on outcome parameters is poorly defined. Furthermore, persisting epilepsy significantly influences the patients’ quality of life (QoL). This study aims at specifically evaluating the impact of epilepsy in elderly GBM patients.

Material and Methods

Two Austrian academic neurosurgical centers retrospectively analyzed all elderly (≥65 years) GBM patients with de-novo tumors, who underwent tumor resections between 09/2006 and 07/2021. Epidemiological, histopathological and survival data were gained from patients’ electronic charts and screened for presence of epilepsy preoperatively or during follow-up.

Results

391 patients (55% males, 45% females) with a median age at surgery of 73 years (Interquartile Range (IqR) 68.5-77.5) were analyzed. The mean predicted OS was recorded to be 12.4 months (CI95% 10.9-14.0). Median preoperative Modified Rankin Scale (mRS) was 2 (IqR 1-3), and median preoperative Karnofsky performance score was 80 (IqR 60-90). Mean follow-up was 10.4 months (CI95% 9.1-11.6) in our cohort. 95/391 patients (24%) suffered from preoperative epilepsy. 17 (18%) patients still suffered from epilepsy after tumor resection with eight patients who developed new postoperative seizures, and four patients (1.0%) showed a worsening of already preoperatively diagnosed seizures. Major surgery-associated neurological complications included new motor deficits in 29 (7%) and new aphasia in 16 (4%) patients. Logistic regression showed, patients with seizures had significantly lower mRS (OR=0.735 [CI95% 0.563 0.961], p=0.032) and less frequently occipital tumor location (OR=0.347 [CI95% 0.152-0.791], p=0.018). Postoperative epilepsy resulted in significantly prolonged hospitalization after the surgery (OR=2.622[CI95% 1.496-3.979], p=0.009). Survival did not correlate with preoperative epilepsy (p>0.05). However, Cox regression revealed that multifocal tumor location (HR=1.777 [CI95% 1.197-2.639], p=0.025) as well as thalamic involvement (HR=11.121 [CI95% 3.431-36,046], p=0.030) negatively influenced OS. Furthermore, surgery-associated complications shortened OS significantly (HR=1.945 [CI95% 1,296-2,916], p=0.025).

Conclusion

Even though epilepsy was not found to directly impact survival in elderly GBM patients, we found that surgery 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.

A patient with two gliomas with independent oligodendroglioma and glioblastoma biology proved by DNA-methylation profiling: a case report and review of the literature

Here, we report on a patient presenting with two histopathologically distinct gliomas. At the age of 42, the patient underwent initial resection of a right temporal oligodendroglioma IDH mutated 1p/19q co-deleted WHO Grade II followed by adjuvant radiochemotherapy with temozolomide. 15 months after initial diagnosis, the patient showed right hemispheric tumor progression and an additional new left frontal contrast enhancement in the subsequent imaging. A re-resection of the right-sided tumor and resection of the left frontal tumor were conducted. Neuropathological work-up showed recurrence of the right-sided oligodendroglioma with features of an anaplastic oligodendroglioma WHO Grade III, but a glioblastoma WHO grade IV for the left frontal lesion. In depth molecular profiling revealed two independent brain tumors with distinct molecular profiles of anaplastic oligodendroglioma IDH mutated 1p/19q co-deleted WHO Grade III and glioblastoma IDH wildtype WHO grade IV. This unique and rare case of a patient with two independent brain tumors revealed by in-depth molecular work-up and epigenomic profiling emphasizes the importance of integrated work-up of brain tumors including methylome profiling for advanced patient care.

Genotypical glioblastoma of the frontal lobe mimicking ganglioglioma: A case report and review of the literature

This case of severe phenotype-genotype mismatch brain tumor morphologically mimicking benign ganglioglioma emphasizes the urgent need for advanced molecular profiling in brain tumor diagnosis in the era of sophisticated molecular profiling.