1. Department of Internal Medicine, Harbin Medical University Cancer Hospital, Harbin Medical University, Harbin, Heilongjiang, China
2. Department of Gastrointestinal Medical Oncology, Harbin Medical University Cancer Hospital, Harbin, Heilongjiang, China
3. Department of Endoscopy, Harbin Medical University Cancer Hospital, Harbin Medical University, Harbin, Heilongjiang, China
4. Department of Interventional Medicine, The First Affiliated Hospital, Harbin Medical University, Harbin, Heilongjiang, China