Although a decrease in the tumour perfusion by growth inhibition was reported on DCE-US following treatment with the mTOR inhibitor everolimus (5 mg kg–1 for 3 weeks) (Broillet et al, 2005), other data show that Ktrans did not change in everolimus-treated tumour models when compared with measurable changes seen with the VEGF inhibitor vatalanib (Lane et al, 2009). This evidence concerns the gene MTOR and neoplasm.