CD40LG and neoplasm: NSCLC lends itself to the study of anti‐tumor immunity owing to its high number of nonsynonymous mutations compared to other tumor types, due to mutagens such as tobacco smoke, thereby providing an avenue for development of anti‐tumor vaccines and immunotherapy.10 In the present study, our primary objective was to investigate whether radiation promotes production of anti‐human antibodies in patients with NSCLC treated with either photon or proton irradiation by measuring IgG and IgM expression in patient plasma samples pre‐ and post‐RT in response to tumor antigens.