2026 Proffered Presentations
S184: SPATIAL DISTRIBUTION AND CHARACTERISTICS OF PEDIATRIC MENINGIOMAS
Casey A Jarvis, MD1; Dylan Keusch, BS2; Aaron Yeo, MD2; Sanda Alexandrescu, MD2; Andres Santos, MD, PhD2; Lissa C Baird, MD2; Wenya Linda Bi, MD, PhD1; 1Brigham and Women's Hospital; 2Boston Children's Hospital
OBJECTIVE: Pediatric meningiomas are known to arise in different anatomic locations than those in adults. In adults, tumor location has been linked to clinical behavior, but this relationship remains poorly characterized in the pediatric population. This study aims to map the spatial distribution of pediatric meningiomas in a large, single-center cohort and to investigate associations with tumor grade, molecular alterations, and clinical features.
MATERIAL AND METHODS: We performed a single-center retrospective cohort study of pediatric patients (<21yo) with meningioma at Boston Children’s Hospital from 1993-2025. Demographic, histopathologic, molecular, and clinical information was collected. All statistical analysis was conducted in R, using Fisher’s exact test and the Monte Carlo simulation where appropriate.
RESULTS: 74 patients with pediatric meningioma treated at our institution were identified, with a median age at diagnosis of 12.5 years (IQR 8.6–16.7). The majority of tumors were supratentorial (77.0%). The most frequent tumor location was skull base (n=22), followed by intraventricular/non-dural-based tumors (n=17), lateral convexity (n=11), tentorial/falcine (n=8), midline convexity (n=7), optic nerve (n=5), and spinal (n=4). Surgical treatment was performed in 81.1% of cases. Among these, 46.7% were grade I, 48.3% grade II, and 3.3% grade III. Location was associated with WHO grade (p=0.036), with intraventricular tumors more often grade I, skull base tumors split between grades I and II, and midline convexity and tentorial/falcine tumors more frequently grade II. A history of prior cranial radiation was present in 17% of patients n=13) and showed a significant associated with tumor location (p=0.030), most commonly in lateral convexity tumors. Gross total resection (GTR) was achieved in 65% (n=39), near-total resection (NTR) in 3.3% (n=2), subtotal resection (STR) in 23.3% (n=14), and biopsy in 20% (n=6). Extent of resection varied significantly by location (p=0.007), with STR being most common in skull base tumors. Molecular data were available for 32 patients. Monosomy of chromosome 22 was the most frequent alteration (n=17) and was not associated with tumor location (p=0.976). Recurrence was observed in seven patients after surgery and was significantly associated with grade (p=0.025) but not location (p=0.363).
CONCLUSIONS: The spatial distribution of pediatric meningiomas in our cohort differed markedly from adults, with a notable predominance of intraventricular and non-dural-based tumors. Tumor location was significantly associated with a history of prior radiation, which was most frequent in lateral convexity tumors, suggesting distinct biological mechanisms in these patients. Skull base tumors had the highest rates of subtotal resection, likely due to the technical challenges posed by adherence to critical neurovascular structures. While monosomy 22 was the most common molecular alteration, no clear association between genotype and tumor location was observed, possibly reflecting the sample sizes and limited molecular data available for this rare pediatric disease. These findings highlight the unique spatial and clinical characteristics of pediatric meningioma and underscore the need for further studies to better understand their biological and molecular determinants.