1. Department of Otolaryngology‑Head and Neck Surgery, Chonnam National University Medical School and Chonnam National University Hwasun Hospital, Hwasun, Jeonnam 519‑809, Republic of Korea
2. Department of Pathology, Chonnam National University Medical School and Chonnam National University Hwasun Hospital, Hwasun, Jeonnam 519‑809, Republic of Korea
3. Department of Preventive Medicine, Chonnam National University Medical School and Chonnam National University Hwasun Hospital, Hwasun, Jeonnam 519‑809, Republic of Korea
4. Department of Internal Medicine, Chonnam National University Medical School and Chonnam National University Hwasun Hospital, Hwasun, Jeonnam 519‑809, Republic of Korea
5. Department of Radiation Oncology, Chonnam National University Medical School and Chonnam National University Hwasun Hospital, Hwasun, Jeonnam 519‑809, Republic of Korea