[1] European Inst Oncol IRCCS, Dept Radiat Oncol, Milan, Italy
[2] ASST Spedali Civili, Dept Radiat Oncol, Brescia, Italy
[3] Univ Florence, Radiotherapy Unit, Dept Biomed Expt & Clin Sci, Florence, Italy
[4] Policlin S Orsola Malpighi IRCCS AOSP, Dept Radiat Oncol, Bologna, Italy
[5] Ctr Riferimento Oncol Aviano CRO IRCCS, Dept Radiat Oncol, Aviano, Italy
[6] Ctr Riferimento Oncol Aviano CRO IRCCS, Div Nucl Med, Aviano, Italy
[7] Univ Brescia, Dept Otorhinolaryngol Head & Neck Surg, Brescia, Italy
[8] IRCCS, Veneto Inst Oncol, Dept Radiat Oncol, Padua, Italy
[9] Univ Padua, Endocrine Surg Unit, Dept Surg Oncol & Gastroenterol, Padua, Italy
[10] Univ Genoa, Dept Radiat Oncol, Genoa, Italy
[11] IRCCS Osped Policlin San Martino, Genoa, Italy
[12] Univ Brescia, Dept Radiat Oncol, Brescia, Italy
[13] Mirano Hosp, Dept Med Oncol, Mirano, Italy
[14] ASST Monza, Dept Radiat Oncol, Milan, Italy
[15] Univ Milano Bicocca, Milan, Italy
[16] Univ Roma Tor Vergata, Radiat Oncol, Dept Biomed & Prevent, Rome, Italy