1. Department of Radiation Oncology; Institute of Oncology; Ljubljana Slovenia
2. Department of Medical Oncology; Antwerp University Hospital; Edegem Belgium
3. Departments of Radiation Oncology, Otolaryngology, and Medical Oncology; Emory University School of Medicine; Atlanta Georgia
4. Department of Hematology and Medical Oncology; The Winship Cancer Institute of Emory University; Atlanta Georgia
5. Department of Medicine, Division of Oncology; Albert Einstein College of Medicine, Montefiore Medical Center; Bronx, New York
6. Fondazione IRCCS Istituto Nazionale dei Tumori; Milan Italy
7. Department of Internal Medicine; University of Michigan Comprehensive Cancer Center; Ann Arbor Michigan
8. Department of Radiation Oncology; University Medical Center Groningen, University of Groningen; Groningen The Netherlands
9. Department of Radiation Oncology; University of Michigan; Ann Arbor Michigan
10. Department of Radiation Oncology; University of Florida; Gainesville Florida
11. Center of Clinical Oncology; University of Hong Kong - Shenzhen Hospital; Shenzhen China
12. Department of Radiation Oncology; Beth Israel Medical Center and St Luke's-Roosevelt Hospitals, New York; New York
13. Department of Otolaryngology-Head and Neck Surgery; University of Michigan; Ann Arbor Michigan
14. Department of Radiation Oncology; The Prince of Wales Cancer Centre; Sydney New South Wales Australia
15. Departments of Surgery and Otolaryngology-Head and Neck Surgery; Albert Einstein College of Medicine, Montefiore Medical Center; Bronx, New York
16. University of Udine School of Medicine; Udine Italy