Gamma knife stereotactic radiosurgery for neurofibromatosis 2 (NF2)-associated meningiomas; a systematic review and meta-analysis

BackgroundNeurofibromatosis type 2 (NF2)-related schwannomatosis is a rare genetic disorder associated with meningiomas. Stereotactic radiosurgery (SRS) has emerged as a potential non-invasive method. This study aims to synthesize the available evidence on using SRS to treat these tumors.MethodsPubMed/Medline, Embase, Scopus, and Web of Science were searched until March 21, 2024. This study was prepared by adhering to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA).ResultsFour studies were included comprising 101 patients with NF2-associated meningiomas treated with SRS. All included studies used gamma knife stereotactic radiosurgery (GKRS) as treatment modality. Overall survival rates remained high (100%) up to 3 years post-treatment, with slight declines at five years of 98% (95% CI: 0.95-1.01) and ten years of 68% (95% CI: 0.48-0.87). Progression-free survival rates were similarly favorable, with 95% (95% CI: 89-101%) at three years, 93% (95% CI: 86-99%) at five years, and 81% (95% CI: 51-111%) at ten years. The pooled radiation necrosis rate was 5% (95% CI: 3-7%), while the overall radiation toxicity rate was 16% (95% CI: 11-21%). Local tumor control rates were high at six months, and at 12 months, they were 100% (95% CI: 1.00-1.00).ConclusionGKRS demonstrates high efficacy and a favorable safety profile for NF2-associated meningiomas, offering a valuable treatment option for this challenging patient population.