Intraoperative Meningioma Consistency Is Not Associated with Surgical Outcomes: A Single-Center Retrospective Cohort Study

Abstract The objective of this study is to evaluate the relationship between intraoperative meningioma consistency, surgical and long-term oncological outcomes, and molecular parameters in a large, single-center patient cohort. In this retrospective observational analysis of 262 adult patients with meningioma, tumor consistency was categorized intraoperatively as soft, intermediate, or firm. Primary outcomes included extent of resection, perioperative complications, and progression-free survival (PFS). Molecular analyses including chromosomes 1p and 22q status, DNA methylation class, and RNA-based risk scores, were available in a subset of patients. Statistical significance was defined as p < 0.05, and no variables met prespecified criteria for multivariate analysis. The cohort consisted of 14% soft, 25% intermediate, and 61% firm tumors. On univariate analysis, tumor consistency was not significantly associated with gross total resection rates (soft: 69.5%, p = 0.9; firm: 72.5%, p = 0.5; intermediate as reference), overall complication rates (p = 0.8 and 0.5 for soft and firm tumors, respectively), recurrence rates (p = 0.2 and 0.4), or PFS, with nearly identical Kaplan–Meier curves across consistency groups. Although not statistically significant, intermediate-consistency tumors were associated with a longer mean hospital stay and a higher median surgery duration (6.1 days, 295 minutes) compared with soft (4.6 days, 230 minutes) and firm (4.3 days, 230 minutes) tumors. Molecular analyses demonstrated no significant association with tumor consistency (p > 0.05). Intraoperative meningioma consistency did not independently impact the extent of resection, postoperative morbidity, recurrence, or PFS. Moreover, no associations were identified between tumor consistency and established molecular tumor characteristics. These findings suggest that intraoperative tumor consistency may reflect physical or microstructural properties not captured by current molecular classifiers and may not predict long-term oncological outcomes.