1. Department of Radiation Oncology; Gustave Roussy; Villejuif France
2. Department of Radiotherapy; Policlinico Umberto I “Sapienza” University of Rome; Rome Italy
3. Université Paris-Sud, Faculté de Médecine Kremlin Bicêtre; France
4. Department of Head and Neck Surgery; Gustave Roussy; Villejuif France