Tumor-to-heart ratios (tumormax/heartmean) were calculated to correct for activity remaining in the blood and were 9.99 ± 0.3 (Renca), 9.05 ± 0.4 (4T1), 8.49 ± 0.44 (Sa1N), 8.15 ± 0.44 (CT26), 7.62 ± 0.28 (MC38), 6.61 ± 0.96 (P815) and 5.28 ± 0.68 (B16F10) for 89Zr-DFO-CD4 (Figure 4D). This evidence concerns the gene CD4 and neoplasm.