1. Department of General Surgery, Tianjin Medical University General Hospital, Tianjin, China
2. Department of Gastroenterology, The Second Hospital of Hebei Medical University, Hebei Key Laboratory of Gastroenterology, Hebei Institute of Gastroenterology, Shijiazhuang, China
3. Department of Gastrointestinal Oncology Surgery, The First Affiliated Hospital of Hebei North University, Zhangjiakou, China
4. Department of Colorectal and Anal Surgery, Cangzhou Central Hospital, Cangzhou, China