IL13RA2 and neoplasm: In 201 CCRCCs, age (CSS, P = 0.042), tumor stage (CSS, P = 0.010; RFS, P < 0.001), tumor necrosis (CSS, P = 0.006; RFS, P = 0.054), and IL13Rα2 expression (CSS, P = 0.019; RFS, P = 0.005) were significantly associated with CSS or RFS (Table 3).