1. Department of Radiotherapy, Heping Hospital Affiliated to Changzhi Medical College, Changzhi, P.R China
2. Department of Gastroenterology, The Third Hospital of Mianyang (Sichuan Mental Health Center), Mianyang, P.R China
3. The Second Chest Radiotheropy Department, Shanxi Province Cancer Hospital/ Shanxi Hospital Affiliated to Cancer Hospital, Chinese Academy of Medical Sciences/Cancer Hospital Affiliated to Shanxi Medical University, Taiyuan, P.R China