Prognostic value of surgical resection over biopsy in elderly patients with glioblastoma: a meta-analysis.

PURPOSE: Maximal-safe resection has been shown to improve overall survival in elderly patients with glioblastoma in observational studies, however, the only clinical trial comparing resection versus biopsy in elderly patients with surgically-accessible glioblastoma showed no improvements in overall survival. A meta-analysis is needed to assess whether surgical resection of glioblastoma in older patients improves surgical outcomes when compared to biopsy alone. METHODS: A search was conducted until October 9th, 2023, to identify published studies reporting the clinical outcomes of glioblastoma patients > 65 years undergoing resection or biopsy (PubMed, MEDLINE, EMBASE, and COCHRANE). Primary outcomes were overall survival (OS), progression-free survival (PFS), and complications. We analyzed mean difference (MD) and hazard ratio (HR) for survival outcomes. Postoperative complications were analyzed as a dichotomic categorical variable with risk ratio (RR). RESULTS: From 784 articles, 20 cohort studies and 1 randomized controlled trial met our inclusion criteria, considering 20,523 patients for analysis. Patients undergoing surgical resection had an overall survival MD of 6.13 months (CI 95%=2.43-9.82, p = < 0.001) with a HR of 0.43 (95% CI = 0.35-0.52, p = < 0.00001). The progression-free survival MD was 2.34 months (95%CI = 0.79-3.89, p = 0.003) with a 0.50 h favoring resection (95%CI = 0.37-0.68, p = < 0.00001). The complication RR was higher in the resection group favoring biopsy (1.49, 95%CI = 1.06-2.10). CONCLUSIONS: Our meta-analysis suggests that upfront resection is associated with improved overall survival and progression-free survival in elderly patients with newly diagnosed glioblastoma over biopsy. However, postoperative complications are more common with resection. Future clinical trials are essential to provide more robust evaluation in this challenging patient population.

Memantine as a neuroprotective agent in ischemic stroke: Preclinical and clinical analysis.

The primary mechanism for neuron death after an ischemic stroke is excitotoxic injury. Excessive depolarization leads to NMDA-mediated calcium entry to the neuron and, subsequently, cellular death. Therefore, the inhibition of the NMDA channel has been proposed as a neuroprotective measure in ischemic stroke. The high morbimortality associated with stroke warrants new therapies that can improve the functional prognosis of patients. Memantine is a non-competitive NMDA receptor antagonist which has gained attention as a potential drug for ischemic stroke. Here we analyze the available preclinical and clinical evidence concerning the use of memantine following an ischemic stroke. Preclinical evidence shows inhibition of the excitotoxic cascade, as well as improved outcomes in terms of motor and sensory function with the use of memantine. The available clinical trials of high-dose memantine in patients poststroke have found that it can improve patients' NIHSS and Barthel index and help patients with poststroke aphasia and intracranial hemorrhage. These results suggest that memantine has a clinically relevant neuroprotective effect; however, small sample sizes and other study shortcomings limit the impact of these findings. Even so, current studies show promising results that should serve as a basis to promote future research to conclusively determine if memantine does improve the outcomes of patients' post-ischemic stroke. We anticipate that future trials will fill current gaps in knowledge, and these latter results will broaden the therapeutic arsenal for clinicians looking to improve the prognosis of patients poststroke.