1 Department of Radiation Oncology, Ghent University Hospital and Ghent University, Ghent B-9000, Belgium. Electronic address: yolande.lievens@uzgent.be.
2 Department of Surgery, Sahlgrenska University Hospital, Gothenburg, Sweden.
3 Patient Advisory Committee, European Cancer Organisation, Brussels, Belgium.
4 Statistics Department, European Organisation for Research and Treatment of Cancer, Brussels, Belgium.
5 Department of Oncology and Danish Centre for Particle Therapy, Aarhus University Hospital, Aarhus, Denmark.
6 International Brain Tumour Alliance, Surrey, UK.
7 Policy Division, European Organisation for Research and Treatment of Cancer, Brussels, Belgium.
8 Department of Clinical Oncology, Guy's & St Thomas' NHS Trust, London, UK; Institute of Cancer Policy, King's College London, London, UK.