Role of early assessment of antiangiogenic treatment in metastatic colorectal cancer using quantitative contrast-enhanced ultrasonography

Abstract

Objective To investigate the application of contrast-enhanced ultrasonograhy(CEUS) in the early assessment of antiangiogenic treatment in metastatic colorectal cancer. Methods Among 41 colorectal cancer patients with liver metastases enrolled in this study, 25 patients received treatment of antiangiogenic treatment(bevacizumab) combined with chemotherapy (BV group) and 16 patients received chemotherapy only (non-BV group). To assess the treatment responses in the liver lesions between and within these two groups, CEUS scans were performed before the treatment (T0 or baseline ), on the day 2 (T1), and on the day 7 (T2) after the treatment. The percentage differences were evaluated according to the CEUS quantitative parameters, such as rise time(RT), peak intensity(PI), mean transit time(MTT), area under the curve(AUC), time from peak to one half(TPH), wash in slope(WIS), and time to peak(TTP). Results On T1, both the RT and MTT increased within the BV group and decrease within the non-BV group, when compared with their own baselines, the differences were statistically significant (P 0.05). Conclusions CEUS can be used to assess the treatment response in liver metastatic patients with colorectal cancer, by monitoring the change of the tumor perfusion before and after the treatment. Key words: Contrast-enhanced ultrasonography; Colorectal neoplasms; Bevacizumab; Response evaluation