1. Department of Family Medicine, Seoul National University College of Medicine, Seoul, Korea.
2. Health Promotion Center for Cancer Survivor, Seoul National University Hospital, Seoul, Korea.
3. Department of Surgery, Seoul National University College of Medicine, Seoul, Korea.
4. Division of Surgery, Thyroid Cancer Center, Seoul National University Hospital, Seoul, Korea.
5. Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Korea.
6. Division of Internal Medicine, Thyroid Cancer Center, Seoul National University Hospital, Seoul, Korea.