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Published on: May 9, 2022
Comparative Analysis of the Prognostic Value of Simpson Grade Versus MRI-Based Extent of Resection Paradigms Across
Nadeem N Al-Adli1, Felix Ehret2,3,4, Minh P Nguyen1,5,6
1Department of Neurological Surgery, University of California San Francisco, San Francisco, California, USA.
Background And Objectives:
Extent of resection (EOR) predicts local freedom from recurrence (LFFR) for meningiomas and is a key clinical trial design parameter. Simpson grade (SG) defines EOR based on intraoperative assessment of tumor removal, but MRI-based methods represent promising alternatives. The aim of this study was to compare the prognostic performance of SG vs MRI-based EOR paradigms for predicting recurrence and survival across histomolecular subgroups.
Methods:
International multicenter, retrospective cohort study included 475 meningiomas, resected between 1983 and 2024, which were classified by World Health Organization grade and molecular subgroups (DNA methylation, gene expression, and integrated grade). Area under the curve (AUC) was calculated for LFFR and overall survival (OS) from Cox models with a histomolecular subgroup and an EOR paradigm. Delta AUC (ΔAUC) compared EOR predictive performance within each subgroup, and log-rank comparisons of LFFR and OS were performed.
Results:
MRI-defined gross total resection was associated with significantly longer LFFR and OS when compared with subtotal resection across most histomolecular subgroups. SG1-3 vs 4 distinguished differences in LFFR across several subgroups, but there were no consistent differences in outcomes when comparing degrees of dural treatment. Multivariable Cox including gene expression groups revealed that volumetric EOR (%) had a significantly higher AUC than SG (ΔAUC 0.07, P = .036) for 5-year OS; otherwise, there were no other differences between MRI-based or SG EOR paradigms for 5-year LFFR or OS. Additional significant differences for predicting 10-year LFFR all favored MRI-based EOR paradigms.
Conclusion:
Although SG and MRI-based EOR paradigms provide similar prognostic performance for predicting LFFR and OS in the era of molecular classification, MRI-based definitions may be preferred for future clinical trial inclusion criteria.
Insights
Extent of resection (EOR) for meningiomas, assessed by Simpson grade or MRI, impacts recurrence and survival. MRI-based EOR showed better prediction for long-term outcomes, suggesting its preference in clinical trials.
Area of Science:
- Neurosurgery
- Oncology
- Radiology
Background:
- Extent of resection (EOR) is crucial for meningioma recurrence and survival.
- Simpson grade (SG) is the traditional intraoperative EOR assessment.
- MRI-based EOR offers a promising alternative for evaluating tumor removal.
Purpose of the Study:
- Compare prognostic performance of SG vs. MRI-based EOR.
- Evaluate prediction of recurrence and survival across meningioma subgroups.
- Determine optimal EOR assessment for clinical trial design.
Main Methods:
- Retrospective cohort study of 475 meningiomas (1983-2024).
- Classification by WHO grade and molecular subgroups.
- Cox models and AUC analysis to compare EOR paradigms for LFFR and OS.
Main Results:
- MRI-defined gross total resection correlated with better LFFR and OS.
- SG distinguished LFFR differences in some subgroups.
- Volumetric EOR (%) showed higher AUC for 5-year OS than SG.
- MRI-based EOR favored prediction for 10-year LFFR.
Conclusions:
- SG and MRI-based EOR show similar prognostic performance with molecular classification.
- MRI-based EOR may be preferred for future clinical trial criteria.
- Further validation of MRI-based EOR in prospective studies is warranted.
