Exploring Demographic, Clinical, Surgical, and Imaging Features in Relation to CDKN2A/B Status in Meningiomas

Meningiomas are the most common primary intracranial tumors, mostly benign, but some exhibit aggressive behavior. The 2021 WHO classification considers CDKN2A/B homozygous deletion as sufficient for grade 3 designation, highlighting its prognostic significance. It remains unclear whether demographic, clinical, or radiological features can predict deletion status or guide testing.

This retrospective single-center study reviewed patients who underwent surgical resection of intracranial meningiomas from July 2023 to July 2024. Inclusion criteria included histologically confirmed meningiomas, preoperative MRI, and CDKN2A/B testing via FISH. Imaging features assessed were tumor volume, edema, enhancement pattern, diffusion restriction, and CSF cleft preservation. Comparisons between CDKN2A/B-deleted and non-deleted groups were performed using Mann-Whitney U and Fisher's exact or Chi-square tests.

Of 77 patients, 44 (57.1%) underwent CDKN2A/B testing, with 9 (11.6%) showing deletion. Median age was 68 years (range 25-83), and 65% were female. No significant differences between deletion-positive and -negative meningiomas were observed in age (69 vs. 68, P = 0.36), sex (66.7% vs. 65.9% female, P = 0.89), or preoperative tumor volume (21.8 vs. 18.6 mL, P = 0.81). Imaging features and histological grades were similar; Ki-67 index median was 8%. Patients were classified as WHO grade I or II regardless of CDKN2A/B status.

In this cohort, demographic, clinical, or radiological features did not reliably predict CDKN2A/B deletion. Several deletion-positive meningiomas were classified as grade 1 or 2, underscoring the disconnect between morphology and molecular grading. These findings support universal CDKN2A/B testing for accurate WHO classification and risk assessment.