IMPACT OF DNA METHYLATION PROfiLING IN REfiNING MENINGIOMA RECURRENCE RISK STRATIfiCATION AND CLINICAL FOLLOW UP

• Published in: Neuro-oncology (Charlottesville, Va.) Vol. 26; no. Supplement_7; p. vii12
• Main Authors: Bakhsh, Mr Ali, Brandner, Prof Sebastian, Scott, Prof Ian, Jenkinson, Prof Michael, Rathi, Dr Nitika
• Format: Journal Article
• Language: English
• Published: 15.10.2024
• ISSN: 1522-8517; 1523-5866
• DOI: 10.1093/neuonc/noae158.045

Abstract AIMS To assess clinical impact of the additive information gained from Integrated Meningioma Risk Score on the risk of meningioma recurrence. METHOD DNA methylation (Illumina EPIC Array) analysis was performed on all recurrent meningioma tumours, primary tumours CNS5 WHO grade 2, 3 and grade 1 with unusual morphological features from Dec 2021 to Jan 2024. DNA methylation analysis was performed, and data files were processed on the DKFZ Heidelberg Classifier v12.5/6 (molecularneuropathology.org). The output from the classifier including methylation class combined with WHO Grade and chromosomal loss (1p, 6q,14q) was used to produce an integrated meningioma risk score for recurrence. RESULTS 70 meningioma cases were profiled. This included 68 cranial meningiomas, ((WHO grade 1, n=19; recurrences=7), (grade 2, n=47; recurrences =9), (grade 3 n=2; recurrences=1)) and 2 spinal meningiomas (grade 1 n=1, grade2 n=1). 3 tumours were excluded due to poor calibration scores. Of the 67 cases the diagnosis was revised in 1 case following DNA methylation analysis due to presence of CDKN2A/B loss. Molecular-morphologic integrated risk score was calculated for all 67 cases. In 10% of overall patients the predicted risk of meningioma recurrence was increased to either intermediate or high, whilst 32% had the risk lowered mainly from intermediate to low. Interestingly, 1 patient who underwent a gross total resection of a WHO Grade 2 meningioma, experienced recurrence with the integrated meningioma risk score indicating low risk of recurrence, which is contrary to the clinical aggressiveness of the tumour. CONCLUSION Meningioma integrated risk stratification by DNA methylation profiling has shown concordance of integrated risk score with WHO Grade in 58% of cases. In 42% of cases the predicted risk was altered when compared to the WHO Grade alone. These results need to be further validated with long term data on patient outcomes.