[1] Tianjin Med Univ, Canc Inst & Hosp, Tianjin Key Lab Canc Prevent & Therapy, Dept Radiotherapy,Natl Clin Res Ctr Canc, Tianjin, Peoples R China
[2] Tianjin Lung Canc Ctr, Tianjin, Peoples R China
[3] Cangzhou 2 Hosp, Dept Radiotherapy, Hebei Prov Cangzhou Hosp Integrated Tradit & West, Wuhan, Hebei, Peoples R China
[4] Daqing Oilfield Gen Hosp, Daqing, Heilongjiang, Peoples R China
[5] Univ Texas MD Anderson Canc Ctr, Dept Radiat Oncol, Div Radiat Oncol, Houston, TX 77030 USA
[6] Peking Univ, Dept Radiotherapy, Hosp 3, Beijing 100871, Peoples R China