¹Department of Surgery, Kyungpook National University Medical Center, Daegu, ²Department of Surgery, Seoul National University Hospital, Seoul, ³Department of Surgery, Kosin University Gospel Hospital, Busan, ⁴Department of Surgery, Yeouido St. Mary’s Hospital, The Catholic University of Korea College of Medicine, Seoul, ⁵Department of Surgery, Chonnam National University Hwasun Hospital, Gwangju, ⁶Department of Surgery, Seoul National University Bundang Hospital, Seongnam, ⁷Department of Surgery, Ajou University Hospital, Suwon, Korea

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