Matched case-control analysis of outcomes following surgical resection of incidental meningioma.

Abstract

The management of incidentally discovered meningioma remains controversial. We sought to compare outcomes following surgical resection of incidental meningioma to a matched cohort of symptomatic meningiomas. A retrospective single-center case-control study was conducted for patients undergoing resection of incidental meningioma from 2000 to 2019. A 1:1 case-control matching for incidental and symptomatic meningioma was performed using the following variables: age at initial visit, gender, tumor location/size, and presence of peritumoral edema. Primary outcomes included (1) WHO grading/histopathological subtype/MIB-1 index, (2) extent of resection (gross total resection or subtotal resection), and (3) recurrence. Outcomes were compared between groups using descriptive/bivariate analyses. A total of 91 incidental meningiomas were analyzed. Trauma was the most common reason (n = 19, 21%) to obtain imaging, and tumor size the leading reason to operate (n = 37, 41%). Median time-to-surgery from initial clinical encounter was 5-months (Q1:3, Q3:16.5). More incidental meningioma patients (n = 47, 52%) were privately insured compared to their matched symptomatic cohort (n = 30, 33%) (P = 0.006). Patients with incidental meningioma had significantly higher mean Karnofsky Performance Scale at time-of-surgery (93.2, SD:11.1 vs. 81.4, SD:12.7) (P < 0.001). There were no significant differences in primary/secondary outcomes between the groups. Incidental meningioma was not associated with recurrence on Cox proportional hazards analysis (HR: 0.795, 95%CI: 0.3-2.1, P = 0.637). Matched case-control analysis demonstrated no significant differences in clinical, histopathological, and functional outcomes following resection of incidental and symptomatic meningioma. While non-operative management with close follow-up and serial imaging is preferred for incidental meningiomas, those undergoing resection when indicated can anticipate similar safety and efficacy as symptomatic meningiomas.