Peking Univ, Canc Hosp, Dept Gastrointestinal Oncol, Beijing 100871, Peoples R China; Fudan Univ, Zhongshan Hosp, Shanghai 200433, Peoples R China; Zhengzhou Univ, Affiliated Hosp 1, Zhengzhou 450052, Peoples R China; Beijing 301 PLA Hosp, Beijing, Peoples R China; Sichuan Univ, Dept Med Oncol, West China Hosp, Chengdu 610064, Peoples R China; Nanjing Bayi Hosp, PLA Canc Ctr, Nanjing, Jiangsu, Peoples R China; Chinese Acad Med Sci, Canc Inst & Hosp, Beijing 100730, Peoples R China; Zhejiang Univ, Coll Med, Affiliated Hosp 1, Dept Med Oncol, Hangzhou 310003, Zhejiang, Peoples R China; Jilin Prov Canc Hosp, Changchun, Peoples R China; Heilongjiang Prov Canc Hosp, Harbin, Peoples R China; Hebei Tumor Hosp, Shijiazhuang, Peoples R China; Shanghai Jiao Tong Univ, Shanghai Peoples Hosp 1, Shanghai 200030, Peoples R China; Peking Univ, Canc Hosp, Dept Gastrointestinal Oncol, Key Lab Carcinogenesis & Translat Res,Minist Educ, Beijing 100871, Peoples R China