1. Department of Gastroenterology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China
2. Department of Oncology, Weifang People’s Hospital (The First Affiliated Hospital of Weifang Medical University), Weifang, Shandong, China
3. Department of Epidemiology and Biostatistics, College of Public Health, Zhengzhou University, Zhengzhou, China
4. Department of Radiology, Harefield Hospital, Harefield, United kingdom