1. Department of Surgery, Yonsei University College of Medicine, Seoul, Korea.
2. Department of Gastric Surgery, Tokyo Medical and Dental University, Tokyo, Japan.
3. Department of Gastrointestinal Surgery, Peking University School of Oncology, Beijing Cancer Hospital and Institute, Beijing, China.
4. Brain Korea 21 PLUS Project for Medical Science, Yonsei University Health System, Yonsei University College of Medicine, Seoul, Korea.