The study consists of two parts: (1) in vivo study, where PBMC were not exposed to ex vivo irradiation, thus detected γ-H2AX foci per cell (fpc) that were induced either by endogenous factors or by RT treatment for NSCLC and (2) ex vivo study, where PBMC collected prior to commencement of RT were exposed ex vivo to 2-Gy irradiation that induced the γ-H2AX response. Here, H2AX is linked to non-small cell lung carcinoma.