SOD1 and lung cancer: The aims of this prospective cohort study were as follows: (1) to evaluate the changes in serum SOD activity, as well as SOD1, and SOD2 concentrations; (2) to assess the implications of these alterations with regard to biochemical variables and clinical data, and (3) to investigate the association between serum SOD activity, SOD1/2 concentrations, and all-cause mortality in patients with lung cancer.