1. Department of Otorhinolaryngology–Head and Neck SurgeryChuncheon Sacred Heart HospitalHallym University College of Medicine Chuncheon Republic of Korea
2. Department of PathologySeoul St. Mary's Hospital, College of MedicineThe Catholic University of Korea Seoul Republic of Korea
3. Department of PathologyHanyang University College of Medicine Seoul Republic of Korea
4. Department of Otorhinolaryngology–Head and Neck SurgeryHanyang University College of Medicine Seoul Republic of Korea
5. Department of Otorhinolaryngology–Head and Neck SurgeryBoramae Medical CenterSeoul National University College of Medicine Seoul Republic of Korea