1. Department of Oncology, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215004, P.R. China
2. Department of General Surgery, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215004, P.R. China
3. Department of Gastroenterology, The Second Affiliated Hospital of Soochow University, Suzhou, Jiangsu 215004, P.R. China