(A) Ultrasound molecular images using BR55 in transgenic mouse model of breast cancer development shows substantially increasing imaging signal in the mammary gland with breast tissue progressing from normal to hyperplasia, ductal carcinoma in situ, and invasive breast cancer, suggesting that the magnitude of imaging signal at the cancer stage may help earlier detection of breast cancer using ultrasound molecular imaging. Reprinted with permission from [32]. (B) In a transgenic mouse model of hepatocellular carcinoma development, VEGFR2-targeted ultrasound imaging allowed diagnosing of dysplastic nodule based on magnitude of imaging signal (lower row) while non-targeted contrast-enhanced ultrasound imaging could not differentiate between healthy and dysplastic liver tissue. Reprinted with permission from [34]. (C) Ultrasound imaging also allows visualization of early pancreatic adenocarcinoma in a transgenic mouse model of spontaneous pancreatic cancer development with small foci of cancer showing substantially higher signal (lower row) than normal pancreatic tissue (upper row) due to strong expression of VEGFR2, suggesting that this technology could be used for screening purposes in high risk populations. Reprinted with permisison from [33]. (D) Examples of transrectal transverse VEGFR2-targeted ultrasound molecular images in two patients with biospy-proven prostate cancer, imaged 11 min following intravenous contrast agent injection. Raw data images (left, showing mixed signal from freely circulating and attached microbubbles) and post-processed images (middle; highligthening signal from stationary (attached) microbubbles) show foci of enhanced signal in the peripheral zone suggesting presence of cancer. Right images show corresponding macroscopy slices following radical prostatectomy with the extent of prostate cancer assess by pathological analysis overlaid in red. Reprinted with permission from [47].