1. Department of Surgery, Research Institute of Clinical Medicine, Jeonbuk National University Hospital, Jeonbuk National University and Biomedical Research Institute, Jeonju, Korea.
2. Department of Surgery, Chosun University Hospital, Gwangju, Korea.
3. Department of Surgery, Bucheon Hospital, School of Medicine, Soonchunhyang University, Bucheon, Korea.
4. Department of Surgery, Pusan National University Yangsan Hospital, Yangsan, Korea.
5. Department of Surgery, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
6. Department of Surgery, Chungbuk National University Hospital, College of Medicine, Chungbuk National University, Cheongju, Korea.
7. Division of Breast and Endocrine Surgery, Department of Surgery, Korea University Hospital, Korea University College of Medicine, Seoul, Korea.
8. Department of Surgery, Gangneung Asan Medical Center, University of Ulsan College of Medicine, Gangneung, Korea.
9. Department of Surgery, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
10. The Korea Central Cancer Registry, National Cancer Center, Goyang, Korea.