IL13RA2 and osteosarcoma: Furthermore, IL-13Rα2 positivity was an independent indicator of shorter OS (HR: 11.985; 95% CI: 2.600–55.254; p = 0.001) and RFS (HR: 7.461; 95% CI: 1.946–28.605; p = 0.003) for osteosarcoma patients who had received adjuvant chemotherapy in multivariate analysis (Table 4).