Pediatric meningioma: a clinicopathologic and molecular study with potential grading implications

Area of Science:

• Neuro-oncology
• Pediatric Oncology
• Genetics

Background:

• Meningiomas are common adult brain tumors but rare in children.
• Pediatric meningiomas present unique clinical, pathological, and molecular characteristics.
• Adult data may not accurately guide pediatric meningioma management.

Purpose of the Study:

• To analyze clinical, pathological, and molecular data of pediatric meningiomas.
• To identify features specific to meningiomas in patients 18 years or younger.
• To establish better prognostic markers for pediatric meningiomas.

Main Methods:

• Retrospective analysis of 50 pediatric meningioma cases (age ≤18 years).
• Clinical and pathological data review.
• Next-generation sequencing on 38 specimens.

Main Results:

• Male predominance and higher proportion of spinal tumors noted.
• Common findings include NF2 mutations and chromosome 22 losses.
• Other genetic variants (SMARCB1, FUBP1, BRAF, TERT, CHEK2, SMAD, GATA3) were infrequent.
• H3K27 hypomethylation was absent.
• A mitotic count of six per 10 high-powered fields identified as an optimal cutoff for recurrence-free survival.

Conclusions:

• Pediatric meningiomas exhibit distinct genetic profiles compared to adult tumors.
• Mitotic count threshold may improve prognostic accuracy for pediatric meningiomas.
• Further validation is needed for adjusted grading thresholds in clinical management.