1. Medical University of Gdańsk; Gdańsk Poland
2. Instituto Nacional de Enfermedades Neoplásicas; Lima Peru
3. AZ Sint-Augustinus; Wilrijk Belgium
4. CHU Sart-Tilman; Liege Belgium
5. Groote Schuur Hospital, University of Cape Town; Cape Town South Africa
6. Academisch Medisch Centrum; Amsterdam The Netherlands
7. Institute for Radiation Oncology Arnhem; Arnhem The Netherlands
8. EORTC Headquarters; Brussels Belgium
9. Hospital of Prato; Prato Italy
10. Institute of Oncology and Radiology of Serbia; Belgrade Serbia