Article Text

External validation and recalibration of an incidental meningioma prognostic model – IMPACT: protocol for an international multicentre retrospective cohort study
  1. Abdurrahman I Islim1,2,
  2. Christopher P Millward1,2,
  3. Rory J Piper3,
  4. Daniel M Fountain4,
  5. Shaveta Mehta1,5,
  6. Ruwanthi Kolamunnage-Dona6,
  7. Usama Ali7,
  8. Shelli Diane Koszdin8,
  9. Theo Georgious9,
  10. Samantha J Mills10,
  11. Andrew R Brodbelt1,2,
  12. Ryan K Mathew11,12,
  13. Thomas Santarius13,14,
  14. Michael D Jenkinson1,2
  15. on behalf of the IMPACT Study Investigators, International Consortium on Meningioma (ICOM) and British Neurosurgical Trainee Research Collaborative (BNTRC)
    1. 1Institute of Systems, Molecular & Integrative Biology, University of Liverpool, Liverpool, UK
    2. 2Department of Neurosurgery, The Walton Centre NHS Foundation Trust, Liverpool, UK
    3. 3Department of Neurosurgery, John Radcliffe Hospital, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
    4. 4Manchester Centre for Clinical Neurosciences, Salford Royal NHS Foundation Trust, Salford, UK
    5. 5Department of Clinical Oncology, The Clatterbridge Cancer Centre NHS Foundation Trust, Wirral, UK
    6. 6Department of Health Data Science, Institute of Population Health, University of Liverpool, Liverpool, UK
    7. 7Clinical Trial Service Unit and Epidemiological Studies Unit, Nuffield Department of Population Health, University of Oxford, Oxford, UK
    8. 8Veterans Affairs Healthcare System, Palo Alto, California, USA
    9. 9Brain Tumor Charity, Fleet, UK
    10. 10Department of Neuroradiology, The Walton Centre NHS Foundation Trust, Liverpool, UK
    11. 11Leeds Institute of Medical Research at St James’s, University of Leeds School of Medicine, Leeds, UK
    12. 12Department of Neurosurgery, Leeds Teaching Hospitals NHS Trust, Leeds, UK
    13. 13Department of Neurosurgery, Addenbrooke’s Hospital, Cambridge, UK
    14. 14Division of Neurosurgery, University of Cambridge School of Clinical Medicine, Cambridge, UK
    1. Correspondence to Dr Michael D Jenkinson; Michael.Jenkinson{at}; Dr Abdurrahman I Islim; a.islim{at}


    Introduction Due to the increased use of CT and MRI, the prevalence of incidental findings on brain scans is increasing. Meningioma, the most common primary brain tumour, is a frequently encountered incidental finding, with an estimated prevalence of 3/1000. The management of incidental meningioma varies widely with active clinical-radiological monitoring being the most accepted method by clinicians. Duration of monitoring and time intervals for assessment, however, are not well defined. To this end, we have recently developed a statistical model of progression risk based on single-centre retrospective data. The model Incidental Meningioma: Prognostic Analysis Using Patient Comorbidity and MRI Tests (IMPACT) employs baseline clinical and imaging features to categorise the patient with an incidental meningioma into one of three risk groups: low, medium and high risk with a proposed active monitoring strategy based on the risk and temporal trajectory of progression, accounting for actuarial life expectancy. The primary aim of this study is to assess the external validity of this model.

    Methods and analysis IMPACT is a retrospective multicentre study which will aim to include 1500 patients with an incidental intracranial meningioma, powered to detect a 10% progression risk. Adult patients ≥16 years diagnosed with an incidental meningioma between 1 January 2009 and 31 December 2010 will be included. Clinical and radiological data will be collected longitudinally until the patient reaches one of the study endpoints: intervention (surgery, stereotactic radiosurgery or fractionated radiotherapy), mortality or last date of follow-up. Data will be uploaded to an online Research Electronic Data Capture database with no unique identifiers. External validity of IMPACT will be tested using established statistical methods.

    Ethics and dissemination Local institutional approval at each participating centre will be required. Results of the study will be reported through peer-reviewed articles and conferences and disseminated to participating centres, patients and the public using social media.

    • neurological oncology
    • neurosurgery
    • neuroradiology
    • oncology

    This is an open access article distributed in accordance with the Creative Commons Attribution 4.0 Unported (CC BY 4.0) license, which permits others to copy, redistribute, remix, transform and build upon this work for any purpose, provided the original work is properly cited, a link to the licence is given, and indication of whether changes were made. See:

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    • Twitter @AI_Islim, @CM_Neurosurgeon, @roryjpiper, @shaveta_mehta, @samneurorad, @LeedsNeuro, @jenkinsonmd

    • Collaborators IMPACT Study investigators: Mohamed Abdelsadg, Suhaib Abualsaud, Amro Abuleil, Kevin Agyemang, Hanan Akbari, Likhith Alakandy, Erminia Albanese, Clarissa Alfonso, Usama Ali, Arousa Ali, Tamara Ali, Michael Amoo, Mohamed A. R. Arbab, Mutiu Asha, Kareem Austin, Khaled Badran, Jarnail Bal, Chris Barrett, Parameswaran Bhattathiri, Paul M. Brennan, Andrew R. Brodbelt, Jennifer Brown, Daniel Brown, Ferran Brugada-Bellsolà, Placido Bruzzaniti, Annabel Butcher, Rory S. Cairns, Michael Canty, Michael Cearns, Sachiv Chakravarti, Rebecca Chave-Cox, Yasir Chowdhury, Anna Craig-McQuade, Giles Critchley, Peter Crossley, Elizabeth Culpin, Alessia D'Amico, Bassam Dabbous, Pedro David Delgado-López, Mohamed Draz, Katharine J. Drummond, Rusiru T. Ekanayaka, Muhammed Elhadi, Ibrahim Elmaadawi, Omar Elmandouh, Mazin Elsharif, Daisy Evans, Andreas Fahlström, Pietro Familiari, Fleur L. Fisher, Bryony Ford, Daniel M. Fountain, Keiko Fox, Francesco Gaillard, Chloé Gelder, Theo Georgious, Shamayitri Ghosh, Aimee Goel, Melissa Gough, Athanasios Grivas, Andrew Gvozdanovic, Allan Hall, Hytham Hamid, Liv Hartrick, Samih Hassan, Jack Henry, Damian Holliman, Abdurrahman I. Islim, Asgeir S. Jakola, Mohsen Javadpour, Michael D. Jenkinson, Sanjeeva Jeyaretna, Adrian Jimenez, Josephine Jung, Andranik Kahramanian, Neeraj Kalra, David O. Kamson, Oliver Kennion, Adham M. Khalafallah, Sarah Kingdon, Ruwanthi Kolamunnage-Dona, Shelli Diane Koszdin, Howra Ktayen, Aditaya Kumar, Simon Lammy, Pierfrancesco Lapolla, Jun Yi Lau, Jing Xian Lee, Ryan Leyden, Patricia Littlechild, Sophie Liu, Darmanin Lora-Kay, Vivia Lung, Stephen T. Magill, Hani J. Marcus, Fawaz E. Marhoom, Javier Martin-Alonso, Ryan K. Mathew, Calan Mathieson, Nathan McSorley, Tobias Mederer, Shaveta Mehta, Torstien R. Meling, Samantha J. Mills, Christopher P. Millward, Andrea Mingoli, Mujtaba Mohammad, Debraj Mukherjee, Amir H. Zamanipoor Najafabadi, Olivia Näslund, Minh Nguyen, Imran Noorani, Gildas Patet, Omar N. Pathmanaban, Andrea Perera, Amit Persad, See Yung Phang, Rory J. Piper, Jonathan Pollock, Benjamin Price, Martin Proescholdt, Richard Pullicino, James Robins, Ola Rominiyi, David Rowland, Bobby Sachdev, Fozia Saeed, Mahmoud Saleh, Thomas Santarius, Antonio Santoro, Ieva Sataite, Antony Kevin Scafa, Verena Schadewaldt, Syed Wajahat Shah, Mustafa El Sheikh, Zenab Sher, Bente Sandvei Skeie, Alexander Smedley, Agbolahan Sofela, Jerome St George, Torbjørn Strømsnes, Nigel Suttner, William Taylor, Philip Theodosopoulos, Elliot Tilling, Manjul Tripathi, Ismail Ughratdar, James Ulrich, Adithya Varma, Anil Varma, Maria Velicu, Sara Venturini, Esther Wu, Jacob Young, Giuseppa Zancana, Catherine Zhang. International Consortium on Meningioma (ICOM): Karolyn Au, Jill Barnholtz-Sloan, Felix Behling, Linda Bi, Priscilla Brastianos, Chaya Brodie, Nicholas Butowski, Ana Castro, Aaron Cohen-Gadol, Marta Couce, Francesco Dimeco, Katherine J. Drummond, Ian Dunn, Craig Erker, Michelle Felicella, Daniel M. Fountain, Eva Galanis, Norbert Galldiks, Caterina Giannini, Roland Goldbrunner, Oliver Hanemann, Christel Herold-Mende, Luke Hnenny, Craig Horbinski, Raymond Huang, Abdurrahman I. Islim, Mohsen Javadpour, Michael D. Jenkinson, Christine Jungk, Gerhard Jungwirth, Timothy Kaufmann, Boris Krischek, Sylvia Kurz, Daniel Lachance, Christian Lafougere, Katrin Lamszus, Ian Lee, Serge Makarenko, Tathiana Malta, Tiit Illimar Mathiesen, Christian Mawrin, Michael McDermott, Christopher P. Millward, Jennifer Moliterno-Gunel, Andrew Morokoff, Farshad Nassiri, HK Ng, Houtan Noushmehr, Omar N. Pathmanaban, Arie Perry, Laila Poisson, Bianco Pollo, Aditya Ragunathan, David Raleigh, Mirjam Renovanz, Franz Ricklefs, Felix Sahm, Andrea Saladino, Antonio Santacroce, Thomas Santarius, Christian Schichor, Nils Schimdt, Jens Schittenhelm, Warren Selman, Helen Shih, Andrew Sloan, Matija Snuderl, Jim Snyder, Erik Sulman, Suganth Suppiah, Ghazaleh Tabatabai, Marcos Tatagiba, Marco Timmer, Jorg-Christian Tonn, Michael Vogelbaum, Andreas Von Deimling, Tobias Walbert, Simon Walling, Justin Z. Wang, Patrick Wen, Manfred Westphal, Stephen Yip, Gabriel Zada, Gelareh Zadeh, Viktor Zherebitskiy. British Neurosurgical Trainee Research Collaborative (BNTRC): Daniel M. Fountain, Michael T.C. Poon, Angelos Kolias, Julie Woodfield, Rory Piper, Aswin Chari, Abdurrahman I. Islim, Neeraj Kalra.

    • Contributors AII, SJM, ARB and MDJ conceived the study. AII drafted the initial study protocol. CPM, RJP, DMF, SM, RK-D, UA, SDK, TG, SJM, ARB, RKM, TS and MDJ provided advice and input on the final protocol. All authors proofread and approved the final manuscript.

    • Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

    • Competing interests AII is supported by Health Education England (North West) Academic Foundation Programme. CPM is a PhD candidate funded by The Brain Tumour Charity to complete The COSMIC project. DMF is funded by a National Institute for Health Research Academic Clinical Fellowship and Cancer Research UK Predoctoral Bursary. TS founded and leads the Anaplastic Meningioma International Consortium (AMiCo). TS and MDJ cofounded the British-Irish Meningioma Society (BIMS). MDJ received a grant from the National Institute for Health Research Health Technology Assessment programme for the Radiation vs Observation for Atypical Meningioma (ROAM) trial (NIHR ID: 12/173/14). MDJ and SJM received a grant from the National Institute for Health Research Health Technology Assessment programme for Surgeons Trial Of Prophylaxis for Epilepsy in seizure naïve patients with Meningioma (STOP'EM) (NIHR ID: NIHR129748).

    • Provenance and peer review Not commissioned; externally peer reviewed.

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