1. Department of Surgery, Seoul National University Hospital, Seoul, Korea.
2. Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea.
3. Thyroid Center, Seoul National University Cancer Hospital, Seoul, Korea.
4. Department of Surgery, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, Seoul, Korea.
5. Department of Pathology, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.
6. Department of Internal Medicine, Seoul National University Hospital, Seoul National University College of Medicine, Seoul, Korea.