1. Department of Gastrointestinal Surgery, Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, The Sixth Affiliated Hospital, Sun Yat‑sen University, Guangzhou, Guangdong 510655, P.R. China
2. Department of Digestion, Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases, The Sixth Affiliated Hospital, Sun Yat‑sen University, Guangzhou, Guangdong 510655, P.R. China
3. Gastrointestinal Endoscopy Center, The Eighth Affiliated Hospital, Sun Yat‑sen University, Shenzhen, Guangdong 518033, P.R. China