Proliferation patterns across meningioma locations: A WHO grade-based analysis

Area of Science:

• Neuro-oncology
• Pathology
• Central Nervous System Tumors

Background:

• Meningiomas are the most common primary tumors of the central nervous system.
• Tumor behavior is linked to histopathological grade and proliferative activity.
• Accurate grading and risk stratification are crucial for patient management.

Purpose of the Study:

• To investigate the associations between World Health Organization (WHO) grade, tumor location, mitotic activity, and Ki-67 labeling index in meningiomas.
• To determine the utility of proliferation markers in meningioma risk stratification.

Main Methods:

• Retrospective analysis of 298 surgically treated primary meningiomas (2013-2025).
• Re-evaluation according to the 2021 WHO Classification of Central Nervous System Tumors.
• Assessment of mitotic counts and Ki-67 labeling indices in hotspot areas; statistical analysis and ROC analyses for cut-off values.

Main Results:

• 55.0% Grade 1, 41.6% Grade 2, 3.4% Grade 3 meningiomas identified.
• Both mitotic counts and Ki-67 labeling index significantly increased with WHO grade (ρ=0.79, P<.001).
• Convexity meningiomas showed higher grades and proliferation; skull base/spinal tumors had lower grades and proliferation.

Conclusions:

• Proliferation markers (mitotic activity, Ki-67) strongly correlate with meningioma WHO grade.
• Tumor location is associated with grade and proliferative activity.
• Combined assessment of proliferation markers and location enhances meningioma risk stratification.