Figure 5.

Graphs show correlations between 24-hour changes in MR imaging–assayed vascular leakiness (ΔK^PS) after only a single dose of angiogenesis inhibitor or control saline and fractional tumor growth rate at the completion of an 11-day four-dose treatment regimen for (a) tumor periphery (Tp) and (b) whole tumor (Tw). Regardless of whether the leakiness was assayed for the whole tumor or for the tumor periphery, correlations between leakiness and fractional tumor growth rate were statistically significant (P < .05). The correlation was notably stronger (R² = 0.74 vs R² = 0.45) for the tissue at the tumor periphery, where angiogenesis is presumed to be most active.