1. Center for Breast Cancer, National Cancer Center, Goyang, Korea.
2. Department of Surgery and Cancer Research Institute, Seoul National University College of Medicine, Seoul, Korea.
3. Department of Surgery, Boramae Medical Center, Seoul, Korea.
4. Department of Surgery, Kangwon National University Hospital, Chuncheon, Korea.
5. Department of Surgery, Bundang Jesaeng Hospital, Seongnam, Korea.
6. Department of Surgery, Breast Cancer Center, Korea Cancer Center Hospital, Seoul, Korea.