1. Department of Radiation Oncology; Institute of Oncology; Ljubljana Slovenia
2. Division of Radiation Oncology; Peter MacCallum Cancer Centre; Melbourne Victoria Australia
3. Department of Radiation Oncology; University of Michigan; Ann Arbor Michigan
4. Department of Medical Oncology; Antwerp University Hospital; Edegem Belgium
5. Department of Radiation Oncology; University of Florida; Gainesville Florida
6. Center of Clinical Oncology; University of Hong Kong - Shenzhen Hospital; Shenzhen China
7. Department of Medicine; Division of Oncology; Albert Einstein College of Medicine; Montefiore Medical Center Bronx New York
8. Departments of Radiation Oncology; Otolaryngology and Medical Oncology; Emory University School of Medicine; Atlanta Georgia
9. Department of Otolaryngology-Head and Neck Surgery; VU University Medical Center; Amsterdam The Netherlands
10. Department of Otolaryngology-Head and Neck Surgery; Radboud University Medical Center; Nijmegen The Netherlands
11. Department of Otolaryngology-Head and Neck Surgery; Newcastle upon Tyne Hospitals; Newcastle upon Tyne United Kingdom
12. Department of Clinical Oncology; Northern Centre for Cancer Care; Freeman Hospital Newcastle upon Tyne United Kingdom
13. Department of Otolaryngology-Head and Neck Surgery; The Mount Sinai Medical Center New York New York
14. Department of Otolaryngology-Head and Neck Surgery; University of Michigan; Ann Arbor Michigan
15. Department of Radiation Oncology; Beth Israel Medical Center and St. Luke's-Roosevelt Hospitals, New York; New York
16. ENT Clinic; University of Udine; Udine Italy