The IL13Rα2-positivity showed a 3.726-fold (95% confidence interval [95% CI]; 1.636–8.489, P = 0.002) greater risk of death and a 3.625-fold (95% CI; 1.806–7.278, P < 0.001) greater risk of relapse or death of RCC patients (Table 2). This evidence concerns the gene IL13RA2 and renal cell carcinoma.