1. Department of Surgery, Chuncheon Sacred Heart Hospital, Hallym University College of Medicine, Chuncheon, South Korea.
2. Department of Surgery, Kyung Hee Medical Center, Kyung Hee University School of Medicine, Seoul, South Korea.
3. Department of Surgery, Kyung Hee University Hospital at Gangdong, Kyung Hee University School of Medicine, Seoul, South Korea.