Amadori M, et al. - The authors sought to examine early changes in tumour perfusion parameters by dynamic contrast-enhanced ultrasonography (D-CEUS) and to identify any correlation with survival and tumour response in patients with metastatic colorectal cancer treated with bevacizumab (B). Findings suggested the utility of D-CEUS for detecting and quantifying dynamic changes in tumour vascularity as early as 15 days after the start of B-based therapy. Despite being possible predictor of progression-free survival, the changes showed no correlation with response or overall survival was found.