NF2 Alteration/22q Loss Is Associated with Recurrence in WHO Grade 1 Sphenoid Wing Meningiomas

Simple Summary Sphenoid wing meningiomas account for 11-20% of all intracranial meningiomas and have a higher recurrence rate than those at other sites. The molecular background of meningiomas has been clarified in recent years; therefore, in this study, we aimed to analyze factors associated with the recurrence of sphenoid wing meningiomas. We found that NF2 alteration/22q loss is associated with recurrence in WHO grade 1 sphenoid wing meningiomas, as well as some radiological findings. Together, our study suggests that genotyping meningiomas could help to inform treatment strategies and play an important role in precision medicine, while the preoperative prediction of genotype from radiological features could influence surgical strategies. Furthermore, appropriate follow-up planning could improve the appropriate distribution of medical resources and provide both medical and economic benefits. Sphenoid wing meningiomas account for 11-20% of all intracranial meningiomas and have a higher recurrence rate than those at other sites. Recent molecular biological analyses of meningiomas have proposed new subgroups; however, the correlation between genetic background and recurrence in sphenoid wing meningiomas has not yet been fully elucidated. In this study, we evaluated the clinical characteristics, pathological diagnosis, and molecular background of 47 patients with sphenoid wing meningiomas. Variants of NF2, AKT1, KLF4, SMO, POLR2A, PIK3CA, TRAF7, and TERT were determined using Sanger sequencing, and 22q loss was detected using multiplex ligation-dependent probe amplification. Alterations were localized at NF2 in 11 cases, had other genotypes in 17 cases, and were not detected in 12 cases. Interestingly, WHO grade 1 meningiomas with NF2 alteration/22q loss (p = 0.008) and a MIB-1 labeling index > 4 (p = 0.03) were associated with a significantly shorter recurrence-free survival, and multivariate analysis revealed that NF2 alteration/22q loss was associated with recurrence (hazard ratio, 13.1). The duration of recurrence was significantly shorter for meningiomas with NF2 alteration/22q loss (p = 0.0007) even if gross-total resection was achieved. Together, these findings suggest that NF2 alteration/22q loss is associated with recurrence in WHO grade 1 sphenoid wing meningiomas.