1. Department of Head and Neck Surgery and Otolaryngology, Asahi University Hospital
2. Radiation Medical Science Center for Fukushima Health Management Survey, Fukushima Medical University
3. Department of Otolaryngology-Head and Neck Surgery, Nara Medical University
4. Department of Head and Neck Surgery, National Cancer Center Hospital
5. Department of Head and Neck Oncology and Surgery, International University of Health and Welfare, Mita Hospital
6. Department of Otolaryngology-Head and Neck Surgery, National Defense Medical College
7. Department of Head and Neck Surgery, Saitama Medical University International Medical Center
8. Department of Otolaryngology, Head and Neck Surgery, Hokkaido University Graduate School of Medicine
9. Department of Otolaryngology, Head and Neck Surgery, Moriyama Memorial Hospital
10. Department of Otolaryngology-Head and Neck Surgery, Tokyo Medical University Hospital
11. Division of Otolaryngology, Head and Neck Surgery, Graduate School of Medical Science, Kanazawa University
12. Department of Pathology and Molecular Diagnostics, Aichi Cancer Center Hospital
13. Department of Otolaryngology, Head and Neck Surgery, Fukushima Medical University
14. Health Care Center, Kouseikai Hospital
15. Department of Head and Surgery, Aichi Cancer Center Hospital