P18.01.A The applicability of established clinical and histopathological risk factors for tumor recurrence during long-term perioperative care in meningioma patients

Abstract Background Risk factors for the prediction of late-onset tumor recurrence in meningioma patients are sparse but needed to estimate duration and control intervals during long-term follow-up patients. In this study, we therefore analyzed value established risk postoperative prognosis a large, single-center series. Material methods Correlations clinical (age, sex, location, extent resection), radiological (postoperative volume) histopathological variables (WHO grade, brain invasion) with relapse were separately after 3, 5, 10 years following microsurgery primary diagnosed intracranial between 1991 2021 uni- multivariate analyses. The prognostic was compared findings entire cohort. Results Within median 29 months (range: 0-307 months), observed 141 (12%) PFS 36 months. among cohort (n=1218) at 15 postoperatively 90%, 84%, 74% 70%, respectively. Among all included, skull base location (HR: 1.51, 95%CI 1.05-2.16; p=.026), Simpson ≥IV resections 2.41, 1.52-3.84; p<.001), high-grade histology 3.70, 2.50-5.47; p<.001) male gender 1.46, 1.01-2.11; p=.042) independent recurrence. Skull 1.92, 1.17-3.17; p=.010 HR: 2.02, 1.04-3.95; p=.038) 1.87, 1.04-3.38; p=.038 2.29, 1.07-4.01; p=.034) not subtotal resection 1.53, .68-3.45; p=.303 1.75, .52-5.96; p=.369) remained independently correlated an event-free least three (n=485) five (n=346), Similarly, volume related (p<.001) beyond ≥ (p>.05). 147 ten years, recurrences occurred, no correlation found any variables. Conclusion should be considered when planning ≥5 surgery. Tumor relapses more than surgery very rare, corresponding predictors lacking.