KDR and neoplasm: In good agreement with this, also the absolute numbers of αSMA+, Col I+, Col IV+ and VEGFR2+ blood vessels (Fig. 2c,d,i,j) correlated better with DY750-labelled PHPMA tumour accumulation than the relative fractions of αSMA+, Col I+, Col IV+ and VEGFR2+ vessels (Supplementary Fig. 3j–n).