1. National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College , Beijing, 100021, China
2. Department of Radiation Oncology, Fujian Medical University Union Hospital , Fuzhou, Fujian, 350001, China
3. Department of Radiation Oncology, the First Medical Center of the People’s Liberation Army General Hospital , Beijing, 100853, China
4. School of Physics, Beihang University , Beijing, 102206, China