DNA methylation-based classification and grading system for meningioma
Profiling the chemical marks on meningioma DNA separated the tumours into six classes that predicted recurrence better than the traditional microscope-based grade, especially for the many grade 1 and 2 tumours that behave unexpectedly.
Overview
Retrospective study of 497 meningiomas (with 309 validation cases) using genome-wide DNA methylation profiling to define six methylation classes and three combined groups (benign, intermediate, malignant), compared with WHO grading for prediction of recurrence.
Methylation classes identified aggressive tumours among WHO grade 1 and 2 cases and benign behaviour among some grade 2 tumours, outperforming histological grade for progression-free survival.
- Six methylation classes with distinct recurrence risk; methylation grouping predicted progression better than WHO grade.
Molecular classification is entering meningioma diagnosis (the 2021 WHO classification incorporates CDKN2A/B deletion and TERT promoter mutation) and is used to select grade 2 patients for or against adjuvant radiotherapy and trials.
- Retrospective; methylation profiling is not universally available.
- Combined integrated grading systems have since refined this approach.