1. Department of Gastrointestinal Surgery, Shandong Provincial Hospital, Cheeloo College of Medicine, Shandong University, Jinan 250021, Shandong, People’s Republic of China
2. Department of Emergency Surgery, The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao 262000, Shandong, People’s Republic of China
3. Department of Gastroenterology, The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao 262000, Shandong, People’s Republic of China
4. Department of PET-CT, The Affiliated Hospital of Qingdao University, Qingdao University, Qingdao 262000, Shandong, People’s Republic of China