An international multicenter matched cohort analysis of incidental meningioma progression during active surveillance or after stereotactic radiosurgery: the IMPASSE study

Abstract

Background The optimal management of patients with an incidental meningiomas remains unclear. The aim of this study was to characterize the radiologic and neurological outcomes of expectant and SRS management of asymptomatic meningioma patients. Methods Using data from 14 centers across 10 countries, the study compares SRS outcomes to active surveillance of asymptomatic meningiomas. Local tumor control of asymptomatic meningiomas and development of new neurological deficits attributable to the tumor were evaluated in the SRS and conservatively managed groups. Results In unmatched cohorts, 727 meningioma patients underwent SRS and were followed for a mean of 57.2 months. In the conservatively managed cohort, 388 patients were followed for a mean of 43.5 months. Tumor control was 99.0% of SRS and 64.2% of conservatively managed patients (p<0.001; OR 56.860 (95%CI 26.253–123.150))). New neurological deficits were 2.5% in the SRS and 2.8% of conservatively managed patients (p=0.764; OR 0.890 (95% CI 0.416–1.904)). After 1:1 propensity matching for patient age, tumor volume, location, and imaging follow-up, tumor control in the SRS and conservatively managed cohorts was 99.4% and 62.1%, respectively (p<0.001; OR 94.461 (95% CI 23.082-386.568)). In matched cohorts, new neurological deficits were noted in 2.3% of SRS treated and 3.2% of conservatively managed patients (p=0.475; OR 0.700 (95% CI 0.263–1.863)). Conclusions SRS affords superior radiologic tumor control compared to active surveillance without increasing the risk of neurological deficits in asymptomatic meningioma patients. While SRS and active surveillance are reasonable options, SRS appears to alter the natural history of asymptomatic meningiomas including tumor progression in the majority of patients treated.

Radiotherapy for meningiomas

“…Within this population, the 5-year progression free survival of patients with subtotally resected WHO grade 1 meningiomas was 72.7%. Similarly, in the multicenter propensity-matched IMPASSE study [ 27 ], imaging defined meningiomas that were presumed to be benign and underwent observation experienced tumor control of 64.2% at a mean of 43.5 months of follow up. Thus, a significant subset of patients with WHO grade 1 meningiomas remain at risk of recurrence with or without resection, but the ideal timing of and indications for radiotherapy, and the optimal factors for selection of patients for escalated management, remain subject to debate.…”

Comparison of Active Surveillance to Stereotactic Radiosurgery for the Management of Patients with an Incidental Frontobasal Meningioma—A Sub-Analysis of the IMPASSE Study

“…IMPASSE was an international, multi-center, retrospective cohort study of patients with an incidental meningioma subject to SRS or active surveillance. The complete study methods have been previously described [ 13 ]. In brief, 14 centers in 10 countries submitted data on 1117 patients who were found to have an incidental meningioma.…”

“…The risk of an adverse event must be weighed against the risk of meningioma growth and development of symptoms. To this end, this sub-analysis of the IMPASSE study [ 13 ], an international multi-center comparative study of incidental meningioma progression following active surveillance or SRS, focuses on comparative outcomes of patients with a frontobasal meningioma subject to either early prophylactic intervention with SRS or active surveillance.…”

MerlinS13 phosphorylation controls meningioma Wnt signaling and magnetic resonance imaging features

“…Bioinformatic investigations have revealed biological drivers and therapeutic vulnerabilities underlying meningiomas with unfavorable outcomes [5][6][7][8][9][10][11][12] , and clinical trials of new therapeutic strategies to treat patients with meningiomas that are resistant to standard interventions are underway 4 . Nevertheless, most meningiomas are benign and many can be safely observed with serial magnetic resonance imaging (MRI) 13 . Imaging surveillance can spare patients from morbidities associated with potentially unnecessary surgical or radiotherapy treatments, but current meningioma classi cation systems rely on histological and molecular analyses of tumor tissue after resection 14 .…”