2026 Poster Presentations
P514: ASPIRIN USE AND TUMOR CONTROL FOLLOWING VESTIBULAR SCHWANNOMA RESECTION: A PROPENSITY-MATCHED ANALYSIS
Rithvik Ramesh, BA1; Lourdes Kaufman, BA1; Ruben Hernandez, BS1; Stephanie Younan, BS, MPH1; Nadeem Al-Adli, MD2; Philip V Theodosopoulos, MD1; Steven W Cheung, MD1; Nicole T Jiam, MD1; Ramin A Morshed, MD1; 1University of California, San Francisco; 2University of North Carolina at Chapel Hill
Introduction: Several preclinical studies have suggested that aspirin may inhibit the growth of vestibular schwannomas through cyclooxygenase-2-mediated pathways. However, the clinical relevance of these findings remains unclear, with prior retrospective studies yielding conflicting results and focusing on observed tumors. Whether aspirin influences outcomes in resected tumors is unknown. Therefore, we investigated the impact of aspirin use on time to tumor progression following resection of vestibular schwannomas.
Methods: Retrospective chart review identified patients who underwent surgical resection of newly diagnosed vestibular schwannomas between 2004 and 2024 at a large urban tertiary care center. Demographic and clinical characteristics were compared between patients with and without chronic aspirin use using appropriate parametric and non-parametric statistical tests. Propensity-score matching of aspirin users and non-users (1:1) was performed according to age, BMI, preoperative radiation, preoperative and postoperative tumor volume, extent of resection (EOR), and postoperative adjuvant radiotherapy. Postoperative progression was defined by growth of residual tumor or tumor recurrence on follow-up MRI. Kaplan-Meier survival curves with log-rank tests were used to assess differences in progression-free survival (PFS) among the matched cohort based on aspirin use, stratified by EOR. Multivariable Cox proportional hazards models were constructed in the subtotal resection (STR) subgroup to identify predictors of PFS, with hazard ratios (HR) and 95% confidence intervals reported.
Results: Our final analytic cohort consisted of 354 patients, of whom 131 (37.0%) used aspirin. Prior to matching, aspirin users were significantly older (Mean Age: 58.2 vs 49.1 years; p<0.001) had higher mean BMI (29.1 vs 26.3 kg/m²; p<0.001), and higher Charlson Comorbidity Index (Median: 2 vs 1; p<0.001) compared to non-users. Aspirin users also presented with smaller tumors (Mean volume: 8.3 vs 11.2 cm3; p=0.017), more commonly underwent gross total resection [GTR] (30.4% vs 15.0%, p<0.001) and less frequently received adjuvant radiotherapy (29.8% vs 49.5%; p<0.001). No significant differences were found in PFS between aspirin users and non-users in the overall matched cohort (Median PFS: Not Reached vs 8.1 years; p=0.097) and among patients with STR (Median PFS: Not Reached vs 8.1 years; p=0.087). No tumors progressed in the GTR subgroup. On Cox regression, aspirin use was not significantly associated with PFS (HR 0.40 [95% CI: 0.14-1.09]).
Conclusions: In this single-institution cohort of surgically resected vestibular schwannomas, aspirin use was not associated with a statistically significant improvement in progression-free survival. No progression occurred after gross total resection regardless of aspirin status, and in the subtotal resection subgroup, aspirin use was not a significant predictor of progression-free survival, with wide confidence intervals reflecting uncertainty in the effect estimate. These findings suggest that aspirin may not meaningfully alter postoperative tumor control and underscore the need for prospective studies to clarify its potential role as an adjunct in vestibular schwannoma management.
