Wei-Xiong Xia1,2, Xing Lv1,2, Hu Liang1,2, Guo-Ying Liu1,2,3, Rui Sun1,2, Qi Zeng4, Si-Wei Li5, Hao-Yuan Mo1,2, Fei Han1,2, Dong-Hua Luo1,2, Qing Liu6, Meng-Yun Shi3, Yan-Fang Ye3, Jing Yang7, Liang-Ru Ke1,2, Meng-Yun Qiang1,2, Wen-Ze Qiu1,2, Ya-Hui Yu1,2, Kui-Yuan Liu1,2, Xin-Jun Huang1,2, Wang-Zhong Li1,2, Shu-Hui Lv1,2, Zhuo-Chen Cai1,2, Jing-Jing Miao1,2, Ling Guo1,2, Ming-Yuan Chen1,2, Ka-Jia Cao1,2, Lin Wang1,2, Chong Zhao1,2, Pei-Yu Huang1,2, Qiu-Yan Chen1,2, Yi-Jun Hua1,2, Lin-Quan Tang1,2, Chao-Nan Qian1,2, Hai-Qiang Mai8,2, Xiang Guo8,2, Yan-Qun Xiang8,2. 1. State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, P.R. China. 2. State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Sun Yat-sen University Cancer Center, Guangzhou, P.R. China. 3. Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou, P.R. China. 4. Department of Radiation Oncology, the Fifth Affiliated Hospital, Sun Yat-Sen University, Zhuhai, P.R. China. 5. Department of Radiation Oncology, the Affiliated Hospital of Guilin Medical University, Guilin, P.R. China. 6. Department of Medical Statistics and Epidemiology, Sun Yat-Sen University Cancer Center, Guangzhou, P.R. China. 7. Department of Radiation Oncology, Shanghai Proton and Heavy Ion Center, Shanghai, P.R. China. 8. State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Sun Yat-sen University Cancer Center, Guangzhou, P.R. China. xiangyq@sysucc.org.cn guoxiang@sysucc.org.cn maihq@sysucc.org.cn.