Low-Dose Acetylsalicylic Acid Treatment in Non-Skull-Base Meningiomas: Impact on Tumor Proliferation and Seizure Burden

SIMPLE SUMMARY: MIB-1 index is an established immunohistochemical marker reflecting the proliferative potential in meningiomas. Cyclooxygenase-2 has been demonstrated to be positively correlated with MIB-1 index in meningiomas. In a recent investigation, we revealed that cranial non-skull-base meningiomas have increased proliferative potential and increased inflammatory burden compared to other anatomical locations of meningiomas. The role of nonsteroidal anti-inflammatory drugs (NSAIDs) regarding proliferative activity and location-specific symptoms in non-skull-base meningiomas is unclear so far. In the present investigation, we therefore analyzed the impact of low-dose (100 mg) acetylsalicylic acid (ASA) treatment on the MIB-1 index and baseline symptomatic epilepsy. We identified that elderly female non-skull-base meningioma patients with ASA intake had significantly lower MIB-1 indices. Furthermore, ASA intake significantly reduced the preoperative seizure burden in non-skull-base meningioma. We believe that further research on NSAID treatment in non-skull-base meningiomas is necessary to enhance a tailored treatment scheduling. ABSTRACT: MIB-1 index is an important predictor of meningioma progression and was found to be correlated with COX-2 expression. However, the impact of low-dose acetylsalicylic acid (ASA) on MIB-1 index and clinical symptoms is unclear. Between 2009 and 2022, 710 patients with clinical data, tumor-imaging data, inflammatory laboratory (plasma fibrinogen, serum C-reactive protein) data, and neuropathological reports underwent surgery for primary cranial WHO grade 1 and 2 meningioma. ASA intake was found to be significantly associated with a low MIB-1 labeling index in female patients ≥ 60 years. Multivariable analysis demonstrated that female patients ≥ 60 years with a non-skull-base meningioma taking ASA had a significantly lower MIB-1 index (OR: 2.6, 95%: 1.0–6.6, p = 0.04). Furthermore, the intake of ASA was independently associated with a reduced burden of symptomatic epilepsy at presentation in non-skull-base meningiomas in both genders (OR: 3.8, 95%CI: 1.3–10.6, p = 0.03). ASA intake might have an anti-proliferative effect in the subgroup of elderly female patients with non-skull-base meningiomas. Furthermore, anti-inflammatory therapy seems to reduce the burden of symptomatic epilepsy in non-skull-base meningiomas. Further research is needed to investigate the role of anti-inflammatory therapy in non-skull-base meningiomas.