Two-stage radiosurgery for large brain metastases: a systematic review and meta-analysis of clinical outcomes.

OBJECTIVE: Brain metastases (BMs) are the most common intracranial tumors. In several cases, they present as large masses, which are related to a worse prognosis and more complex therapeutic alternatives. Staged radiosurgery is reported to achieve local control with minimal radiation-related adverse events in BMs. However, no methodological consensus has been achieved in its use for large brain metastases (LBMs; > 2 cm). Therefore, the authors aimed to determine the effectiveness and safety of 2-stage Gamma Knife radiosurgery (GKRS) for LBMs, in order to optimize patients' postoperative course. METHODS: A systematic review of available literature was run in PubMed/MEDLINE, Scopus, Web of Science, Cochrane (OvidSP), and Google Scholar for works published up to December 14, 2022. Nonrandomized clinical trials, case series, and cohort studies were included. The risk of bias was assessed using the Risk of Bias in Nonrandomized Studies-of Interventions (ROBINS-I) and Joanna Briggs Institute tools. Pooled mean difference and rates estimates were calculated by a random-effects model meta-analysis. The degree of heterogeneity was expressed using the I2 statistic. A subgroup analysis was performed. Ultimately, the certainty of evidence was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) assessment. RESULTS: Fourteen studies met the eligibility criteria (cohorts, case series, and nonrandomized clinical trials), including 958 patients. A total pooled mean volume reduction of 6.27 cm3 (95% CI 5.67-6.88 cm3) and 54.36% (95% CI 39.92%-68.79%) after 2-stage GKRS was reported. Pooled rates of complete response (44.63%; 95% CI 26.50%-64.31%), neurological mortality (16.19%; 95% CI 7.68%-30.98%), and all-cause mortality (47.92%; 95% CI 28.04%-68.49%) were calculated. Overall certainty of evidence ranged from very low to moderate. CONCLUSIONS: Two-stage GKRS is an effective and safe approach for the treatment of LBMs. Nevertheless, the lack of available literature and the weak methodological approaches used determine a low to very low certainty of evidence and cannot provide robust evidence to recommend this intervention. Therefore, it is necessary to conduct higher-quality primary studies.

Endovascular Treatment and Microsurgical Clipping for the Management of Paraclinoid Intracranial Aneurysms: A Systematic Review and Meta-Analysis.

OBJECTIVE: We aimed to compare the efficacy and safety of microsurgical clipping versus endovascular treatment (EVT) for paraclinoid aneurysms. METHODS: A systematic search for studies including patients with paraclinoid aneurysms treated with a microsurgical or endovascular technique was conducted in 6 databases from inception to February 2022. Efficacy outcomes included complete angiographic occlusion at last follow-up, favorable functional outcome, and recurrence of the aneurysm. For safety, we assessed a composite of intraoperative and postoperative complications. Data were pooled using a random-effects model. RESULTS: A total of 95 studies including 6711 patients, 3029 in the surgical group and 3682 in the EVT group were found. Pooled rates of complete occlusion were 94% (95% CI 91%-96%; I2 = 0%) in the surgical group and 69% (95% CI 63%-74%; I2 = 79%) in the EVT group, respectively. The favorable functional outcome rate was 86% (95% CI 76%-92%; I2 = 72%) with surgical treatment and 95% (95% CI 92%-97%; I2 = 61%) with EVT. The rate of aneurysm recurrence with surgical treatment was 1% (95% CI 0%-4%; I2 = 0%) and 12% (95% CI 9%-16%; I2 = 57%) with EVT. The composite safety outcome rate in the surgical group was 24% (95% CI 18%-30%; I2 = 90%) and 10% (95% CI 8%-13%; I2 = 71%) in the EVT group. CONCLUSIONS: Our findings suggest that microsurgical clipping seems to have a higher efficacy than EVT in terms of angiographic occlusion and aneurysm recurrence; however, EVT seems to be safer in terms of intraoperative and postoperative complications. Considering the heterogeneity and low-level evidence of the data available, further prospective randomized studies are warranted to confirm our findings.