1. Department of Gastroenterology, Changhai Hospital, Second Military Medical University, Shanghai 200433, China
2. Department of Pathology, Changhai Hospital, Second Military Medical University, Shanghai 200433, China
3. Department of Radiology, Changhai Hospital, Second Military Medical University, Shanghai 200433, China
4. Department of General Surgery, Changhai Hospital, Second Military Medical University, Shanghai 200433, China