1. Department of Gastrointestinal Surgery, Ruijin Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai, China
2. Shanghai Minimally Invasive Surgery Center, Ruijin Hospital, Shanghai Jiao Tong University, School of Medicine, Shanghai, China
3. Department of Gastrointestinal Surgery, Shanghai Minimally Invasive Surgery Center, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200025, P.R. China