Celebrating Physiology in Ireland (Trinity College Dublin, Ireland) (2026) Proc Physiol Soc 77,
C34
Poster Communications: Defining the glioma peritumoural zone: A multi-disciplinary Delphi consensus establishing the Radiology-Pathology-Distance (RPD) Classification
Vincent Healy1, Alan Beausang2, Philipp Karschnia3, David O'Brien4, Stephen MacNally4, Catherine Moran4, Mohammed B Husien5, Darach Crimmins4, Joanna Fay6,
1Discipline of Physiology, School of Medicine, Trinity College Dublin, Dublin. Ireland., 2Department of Neuropathology, The National Neuroscience Centre, Beaumont Hospital. Ireland, 3Department of Neurosurgery, University Hospital of the Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen. Germany, 4Department of Neurosurgery, The National Neuroscience Centre, Beaumont Hospital, Dublin. Ireland., 5Department of Neurosurgery, The National Neuroscience Centre, Beaumont Hospital, Dublin, Ireland. Department of Neurosurgery, The National Neuroscience Centre, Beaumont Hospital, Dublin. Ireland., 6Department of Molecular Pathology, RCSI University of Medicine and Health Sciences, Royal College of Surgeons in Ireland, Beaumont Hospital, Dublin. Ireland., 7Centre for Clinical Brain Sciences, University of Edinburgh, NHS Lothian, Edinburgh. United Kingdom., 8Immunology Unit, Department of Physiology, Universidad de Extremadura, Cáceres. Spain., 9Hospital Clínic de Barcelona, Universitat de Barcelona, Barcelona. Spain., 10Department of Neurosurgery, University Hospital LMU, Munich. Germany., 11Department of Neurology, University Hospital & University of Zurich, Zurich. Switzerland., 12Division of Neurosurgery, Department of Clinical Neurosciences, University of Cambridge, Cambridge. United Kingdom., 13Department of Radiology and Nuclear Medicine, Erasmus MC University Medical Centre, Rotterdam. The Netherlands., 14Division of Neuro-Oncology, Department of Neuroscience, University of Turin/City of Health and Science Hospital, Turin. Italy., 15Department of Neuropathology, Sorbonne Université/Pitié-Salpêtrière Hospital AP-HP, Paris. France., 16Precision Cancer Medicine Group, RCSI University of Medicine and Health Sciences, Royal College of Surgeons in Ireland, Dublin. Ireland., 17Department of Neuroradiology, The National Neuroscience Centre, Beaumont Hospital, Dublin. Ireland., 18Department of Neurophysiology, Hôpital Fondation Adolphe de Rothschild, Paris. France., 19Center For Neuro-Oncology, Dana-Farber Cancer Institute and Harvard Medical School, Boston, Massachusetts. USA., 20Sorbonne Université, AP-HP, Institut du Cerveau - Paris Brain Institute - ICM, Inserm, CNRS, Hôpitaux Universitaires La Pitié Salpêtrière - Charles Foix, Service de Neuro-Oncologie-Institut de Neurologie, F-75013, Paris. France., 21Discipline of Physiology, School of Medicine, Trinity College Dublin, Dublin. Ireland., 22Trinity College Dublin. Ireland.
View other abstracts by:
- Ballestín, A
- Beausang, A
- Byrne, A
- Idbaih, A
- Acevedo, C
- Moran, C
- Crimmins, D
- O'Brien, D
- O'Brien, DF
- Bielle, F
- Huberfeld, G
- Fay, J
- Tonn, J
- Connor, K
- Sweeney., KJ
- Smits, M
- Weller, M
- Husien, MB
- Cunningham, MO
- Bargalló, N
- Karschnia, P
- Nicholson, P
- Brennan, PM
- Wen, PY
- Rudà, R
- Looby, S
- MacNally, S
- Price, SJ
- (Radiology Pathology Distance), TRC
- Healy, V
Objective
To establish an international, multidisciplinary consensus definition and classification framework for the glioma peritumoural zone (PTZ), applicable to research and clinical practice.
Design
International, multidisciplinary modified Delphi study.
Subjects
Multidisciplinary experts (neurosurgery, neuroradiology, neuropathology, neuro-oncology and pre-clinical science) from 23 countries and 10 professional societies completed two survey rounds (round 1, n=61; round 2, n=80). Distributing societies comprised: European Association of Neurosurgical Societies (EANS), European Society of Neuroradiology (ESNR), European Confederation of Neuropathological Societies (Euro-CNS), Deutsche Gesellschaft für Neurochirurgie (DGNC), Société Française de Neurochirurgie (SFNC), Société Française de Neuroradiologie (SFNR), British Neuro-Oncology Society (BNOS), British Neuropathological Society (BNS), Irish Neuropathology Society (IPNS) and the Society of British Neurological Surgeons (SBNS).
Method
A two-round modified Delphi process was conducted with predefined consensus threshold of ≥70% agreement. Participants were recruited via literature review and distribution via 10 collaborating neuro-oncology societies. Iterative survey rounds refined PTZ definitions and informed development of a unified classification framework.
Results
Consensus supported a three-axis Radiology–Pathology–Distance (RPD) classification. The PTZ was defined radiologically as the zone beyond tumour mass (encompassing both contrast-enhancing and non-contrast enhancing components) on structural MRI (81.81%), pathologically as a transitional zone of variably infiltrated but largely preserved brain parenchyma implicated in tumour infiltration and/or microenvironmental change (84.31%), and spatially by standardized measurement of sampling distance (71.64%). The RPD framework supports integration of annotated datasets through a simple alphanumeric coding framework.
Conclusion
The consensus RPD framework is a clinically-aligned, multi-modal classification system that supports standardised reporting of the glioma peritumoural zone for research and clinical practice.
Where applicable, experiments conform with Society ethical requirements.
