 Basic pre-treatment information will be collected, which included ECOG PS, UICCAJCC stage,primary lesion site, history of smokingcoexisting lung diseasesurgical resection, and pulmonary function test of FEV1VCDLCO. Computed tomography CT of the whole lung in treatment position. Blood test of IL1α,IL1β,IL6,IL7,TGFB and MnSOD by ELISA will be done before and weekly during RT. RT must be given by photon energies 6MV. Radiation lung and esophageal injury will be assessed according to common toxicity criteria adverse effect version3.0 CTCAE-3.0 during RT and in every follow up visits. Genomic DNA is obtained from the blood drawn during RT. Chi-square test, T test, analysis of variance, logistic regression, and proportional hazard ratio method will be used to investigate whether the parameters can be effective in predicting radiation related sequelae. 