1. Department of Internal Medicine, Soonchunhyang University Bucheon Hospital, Bucheon, Korea
2. Department of Surgery, Yongin Severance Hospital, Yongin, Korea
3. Department of Internal Medicine, Chonnam National University Hwasun Hospital, Hwasun, Korea
4. Department of Otolaryngology-Head and Neck Surgery, Chungnam National University Hospital, Daejeon, Korea
5. Department of Surgery, Ewha Womans University Mokdong Hospital, Seoul, Korea
6. Department of Internal Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
7. Department of Surgery, Asan Medical Center, Seoul, Korea
8. Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
9. Department of Radiology, Gangneung Asan Hospital, Gangneung, Korea
10. Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea
11. Department of Surgery, Chung-Ang University Gwangmyeong Hospital, Gwangmyeong, Korea
12. Department of Internal Medicine, Seoul National University Boramae Medical Center, Seoul, Korea
13. Department of Otolaryngology-Head and Neck Surgery, Dankook University Hospital, Cheonan, Korea
14. Department of Otolaryngology-Head and Neck Surgery, Chungnam National University Sejong Hospital, Sejong, Korea
15. Department of Otolaryngology-Head and Neck Surgery, National Cancer Center, Goyang, Korea
16. Department of Radiology, Yeouido St. Mary’s Hospital, Seoul, Korea
17. Department of Internal Medicine, National Cancer Center, Goyang, Korea
18. Department of Radiology, Seoul National University Hospital, Seoul, Korea
19. Department of Internal Medicine, Seoul St. Mary’s Hospital, Seoul, Korea
20. Department of Otolaryngology-Head and Neck Surgery, Gangnam Severance Hospital, Seoul, Korea
21. Department of Internal Medicine, Chung-Ang University Hospital, Seoul, Korea
22. Department of Pathology, Seoul St. Mary’s Hospital, Seoul, Korea
23. Department of Otolaryngology-Head and Neck Surgery, Eunpyeong St. Mary’s Hospital, Seoul, Korea