KDR and neoplasm: However, the concentration in the tumor of the anti-VEGFR2 targeted group at 24 and 72 h post-injection was 32.2 ± 2.8% ID/g and 23.0 ± 1.8% ID/g, respectively, which was significantly higher than that of non-targeted group (26.1 ± 2.5% ID/g and 12.3 ± 1.2% ID/g, respectively, all P < 0.05).