1. Department of General Surgery, The First Affiliated Hospital of Soochow University, Suzhou, 215006 Jiangsu Province, China
2. Department of General Surgery, Affiliated Hospital of Jiangsu University, Zhenjiang, 212001 Jiangsu Province, China
3. Department of Biliary-Pancreatic Surgery, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, China
4. Department of General Surgery, People’s Hospital of Yangzhong, Yangzhong, 212299 Jiangsu Province, China