affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, Sun Yat-sen University (SYSU) - Department of Radiation Oncology, Jilin Province Cancer Hospital, affiliation not provided to SSRN, Government of the People's Republic of China - Xijing Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College (CAMS & PUMC) - Department of Colorectal Cancer Surgery, Chinese Academy of Medical Sciences - National Cancer Center, Chinese Academy of Medical Sciences - National Cancer Center, Chinese Academy of Medical Sciences & Peking Union Medical College (CAMS & PUMC), affiliation not provided to SSRN, Chinese Academy of Medical Sciences - National Cancer Center, affiliation not provided to SSRN, Zhejiang Cancer Hospital, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, Central South University - Hunan Cancer Hospital, Hebei Medical University - Fourth Hospital, Government of the People's Republic of China - Beijing Hospital, affiliation not provided to SSRN, Qinghai Red Cross Hospital, Chinese Academy of Medical Sciences - National Cancer Center, Chinese Academy of Medical Sciences & Peking Union Medical College (CAMS & PUMC) - Department of Radiation Oncology, Chinese Academy of Medical Sciences & Peking Union Medical College (CAMS & PUMC) - Department of Radiation Oncology, Chinese Academy of Medical Sciences - National Cancer Center, Chinese Academy of Medical Sciences - National Cancer Center, Chinese Academy of Medical Sciences & Peking Union Medical College (CAMS & PUMC) - Department of Radiation Oncology and Chinese Academy of Medical Sciences & Peking Union Medical College (CAMS & PUMC)