SOD2 and renal cell carcinoma: According to multivariate Cox proportional hazards models, the presence of metastasis at diagnosis (HR = 6.26, 95% CI = 1.19-33.00, p = 0.031) and high SOD2 expression (HR = 4.97, 95% CI = 1.12–22.02, p =0.035) were significantly associated with shorter CSS intervals in 36 metastatic RCC patients (Table 3).