1. Department of Colorectal Surgery, The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, P. R. China
2. Guangdong Institute of Gastroenterology, The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, P. R. China
3. Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, The Sixth Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, P. R. China
4. Department of Colorectal Surgery, Shengjing Hospital of China Medical University, Shenyang, Liaoning, P. R. China
5. Department of Gastrointestinal Surgery, The First Hospital of Jilin University, Changchun, Jilin, P. R. China
6. Department of Gastrointestinal Surgery, The Affiliated Nanchong Central Hospital of North Sichuan Medical College, Nanchong, Sichuan, P. R. China
7. Department of Gastrointestinal Surgery, The Second People’s Hospital of Yibin, Yibin, Sichuan, P. R. China
8. Department of General Surgery, Daping Hospital, Army Medical university, Chongqing, P. R. China
9. Department of Gastrointestinal Surgery, Renji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, P. R. China
10. Department of General Surgery, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, Beijing, P. R. China
11. Department of Gastrointestinal Surgery, Peking University Cancer Hospital, Beijing, P. R. China
12. Department of Gastrointestinal Surgery, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, Guangdong, P. R. China
13. Ruijin Hospital Shanghai Jiaotong University School of Medicine, Shanghai, P. R. China
14. Department of Gastrointestinal Surgery, Peking University People’s Hospital, Beijing, P. R. China