1. Department of Radiation Oncology, Clinique des Grangettes, Geneva, Switzerland
2. Department of Biometrics, the Netherlands Cancer Institute, Amsterdam, Netherlands
3. Department of Radiation Oncology, Centre Georges-François Leclerc, Dijon, France
4. Department of Radiation Oncology, Radboud university medical center, Nijmegen, Netherlands
5. Department of Radiation Oncology, University Hospitals of Leuven, Leuven, Belgium
6. Department of Radiation Oncology, Institut Curie, Paris, France
7. Department of Radiation Oncology, Institute Verbeeten, Tilburg, Netherlands
8. Department of Radiation Oncology, Medical Center Utrecht, Utrecht, Netherlands
9. Department of Radiation Oncology, Clinique de Genolier, Genolier, Switzerland
10. Department of Radiation Oncology, the Netherlands Cancer Institute, Amsterdam, Netherlands
11. Department of Radiation Oncology, Universitaetsklinikum Köln, Köln, Germany
12. Division of Radiation Oncology, Hôpitaux Universitaires de Genève, Geneva, Switzerland
13. Department of Clinical Oncology, Nottingham University Hospitals NHS Trust, Nottingham, UK
14. Institut Régional du Cancer Montpellier, Montpellier, France
15. Department of Radiotherapy, Clinique et Maternité Sainte Elisabeth, Namur, Belgium
16. Department of Radiotherapy, Clinique La Source, Lausanne, Switzerland
17. EORTC Headquarters, Brussels, Belgium