1. Departments of Radiotherapy and Biostatistics, Institut Gustave Roussy, Villejuif, France
2. Academic Hospital Maastricht/GROW/MAASTRO Clinic, Maastricht, the Netherlands
3. Department of Radiotherapy-Oncology, Centre Hospitalier Lyon Sud, Lyon, France
4. Department of Radiation Oncology, Vrije Universiteit University Medical Center, Amsterdam, the Netherlands
5. Department of Radiation Oncology, Institut Clinic de Malalties Oncohematologiques, Hospital Clinic i Universitari, Barcelona, Spain
6. Department of Oncology, University of Edinburgh, Western General Hospital, Edinburgh, United Kingdom
7. Pneumology Unit, Tenon University Hospital, Paris, France