1. Medical Imaging Center, Harbin Medical University Cancer Hospital, Harbin 150081, P.R. China
2. Department of Radiation Oncology, Xiamen Cancer Center, First Affiliated Hospital of Xiamen University, Xiamen 361000, P.R. China
3. Department of Respiratory Medicine, Harbin Medical University Cancer Hospital, Harbin 150081, P.R. China
4. Department of Radiation Oncology, Harbin Medical University Cancer Hospital, Harbin 150081, P.R. China