1. Graduate School, Xuzhou Medical University, Xuzhou, Jiangsu, P.R. China
2. Department of General Surgery, Nanjing Medical University Affiliated Cancer Hospital, Cancer Institute of Jiangsu Province, Nanjing, Jiangsu, P.R. China
3. Department of General Surgery, Jiangsu Cancer Hospital Affiliated to Nanjing Medical University, Nanjing, Jiangsu, P.R. China
4. Department of General Surgery, The First Affiliated Hospital with Nanjing Medical University, Nanjing, Jiangsu, P.R. China