Fig. 4
PET transaxial images (a, b, please note that the scales in these two images are not the same, which is additionally emphasised by using different colour schemes), histograms of the heterogeneity contributions (the mean intensity deviation per distance calculated according to Eq. 2) (c, d) and surface plots (e, f) in the A431 and SKOV-3 xenografts (with high and intermediate expressions of HER2 targets, respectively) imaged with the tracer 11C-labelled ZHER2:342. These data are from two animals bearing xenografts of similar dimensions. In e and f, the X- and Y-axes represent spatial dimensions and the Z-axis is the uptake in SUVmean