Contrast-enhanced high-frequency ultrasound imaging of early stage liver metastasis in a preclinical mouse model.

Monitoring angiogenesis is potentially an effective strategy for the early detection of cancer. In this study, early detection was achieved by evaluating blood vessel density in the liver using a three-dimensional contrast-enhanced high-frequency ultrasound (CE-HFUS) system and Sonazoid microbubbles. Three-dimensional CE-HFUS detected an increase in blood vessel density in the liver after intrasplenic injection of breast tumor cells into mice. The results were in agreement with immunohistochemical analysis of blood vessel density. Three-dimensional CE-HFUS using microbubbles is an attractive, novel approach for the early detection of liver metastases through quantification of new, pathological vascular growth (i.e. tumor angiogenesis).