2025 Poster Presentations
P140: HYPOFRACTIONATED RADIOSURGERY FOR INTRACRANIAL MENINGIOMA - A SYSTEMATIC REVIEW AND META-ANALYSIS OF LITERATURE
Vinay Jaikumar, MD; Jaims Lim, MD; Seth Schrader, BS, MBA; Michael Liu, BS; Naomi Joseph, BS; Hanna N Algattas, MD; Jason M Davies, MD, PhD; Kenneth V Snyder, MD, PhD; Elad I Levy, MD, MBA; Adnan H Siddiqui, MD, PhD; University at Buffalo Neurosurgery
Introduction: Radiosurgery is a well-established technique used to treat intracranial meningiomas. To mitigate radiation side-effects, fractionation protocols deliver equivalent or higher total radiation in manageable fractions and with favorable side-effect profiles. Hypofractionated stereotactic radiosurgery (HF-SRS) is a fractionation strategy that administers higher doses per fraction, necessitating fewer fractions overall. We performed a systematic review and meta-analysis to evaluate the outcomes of HF-SRS utilization (2-10 fractions) in the treatment of meningiomas.
Methods: PubMed and Embase were systematically reviewed for literature on ‘hypofractionated’ ‘radiosurgery’ for ‘meningiomas.’ Patient/meningioma characteristics, treatment details, and follow-up outcomes were extracted from eligible studies. Meta-analyses were carried out on variables reported by ≥3 studies on R version-4.3.2. Subgroup analyses were conducted for photon-based and proton-based HF-SRS.
Results: We investigated 1714 cases from 25 studies meeting inclusion criteria, representing 27.4% males [24.1-30.9] (Table 1 and 2). Mean age was 57.2 [54.4-60.2] for photon-based patients and 53.7 [52.3-55.1] for proton-based patients (p = 0.03) (Table 2). Mean HF-SRS dose was 23.6 Gy [22.0-25.4] in 4.1 fractions [3.7-4.6] for a mean dose per fraction of 5.8 Gy [5.3-6.4]. Mean isodose line was 75.6% [69.5-82.2] with a conformity index of 1.4 [1.1-1.8]. Partial obliteration rate was 25.2% [17.3-35.1] at 34.7 months [25.5-47.3] of follow-up with an associated 1.7% [1.0-2.8] meningioma-related mortality. Compared to photon-based protocols, proton-based HF-SRS showed comparable meningioma-related mortality (2.6%-vs.-1.6%, p=0.55) and overall survival at one (97.4%-vs.-97.6%, p=0.93), two (97.4%-vs.-97.4%, p=0.99), three (97.4%-vs.-96.7%, p=0.83), and five years (97.4%-vs.-96.4%, p=0.75).
Conclusion: HF-SRS is promising among radiosurgical strategies for meningioma, with no differences in meningioma-related mortality or overall survival between photon or proton-based therapies. Significant heterogeneity regarding HF-SRS dosing strategies warrants additional investigation.