The Correlation between Targeted Contrast-Enhanced Ultrasound Imaging and Tumor Neovascularization of Ovarian Cancer Xenografts in Nude Mice

Abstract

In order to explore the correlation between targeted contrast-enhanced ultrasound imaging and tumor neovascularization of ovarian cancer xenografts in nude mice, a total of 49 nude mice were selected and randomly divided into 1-week group, 2-week group, 3-week group, 4-week group, 5-week group, 6-week group, and 7-week group according to their ovarian cancer xenografts’ growth time, with 7 ovarian cancer xenografts in each group. After preparing antibody-carrying targeted contrast agent, each group of xenografts performed normal and targeted contrast ultrasound examinations to obtain peak intensity, time to peak, and other imaging parameters; then, those ovarian cancer xenografts were sacrificed for pathological analysis: the neovascular density and antibody expression of the cancer xenografts at different stages were observed and counted, and the correlation between targeted contrast-enhanced ultrasound parameters and tumor neovascular densities of the ovarian cancer xenografts was analyzed. The results show that the peak intensities of targeted contrast ultrasound imaging are greater than that of ordinary ultrasound imaging in the 2-, 3-, 4-, and 5-week groups with statistically significant differences ( $P<0.05$ ); the time to peak of targeted contrast ultrasound imaging is shorter than that of ordinary ultrasound imaging in the 2-, 3-, 4-, and 5-week groups with statistically significant differences ( $P<0.05$ ); there is a positive correlation between the peak intensities of targeted contrast ultrasound imaging and tumor neovascular densities of the ovarian cancer xenografts in the 2-, 3-, and 4-week group (r2 = 0.645, r3 = 0.668, and r4 = 0.693, $P<0.05$ ); there is a negative correlation between the time to peak of targeted contrast ultrasound imaging and tumor neovascular densities of the ovarian cancer xenografts in the 2-, 3-, and 4-week groups (r2 = −0.669, r3 = −0.692, and r4 = −0.704, $P<0.05$ ). Therefore, the targeted contrast-enhanced ultrasound imaging parameters have a certain correlation with tumor neovascular density of ovarian cancer xenografts in nude mice and this correlation is more significant in the early stage of ovarian cancer; hence, targeted contrast-enhanced ultrasound imaging may provide a new method, new idea, and new basis for the diagnosis of early ovarian cancer.