Imaging of angiogenesis in metastatic breast cancer by positron emission tomography (PET) using [18F]AH11585, an [18F]- labeled alphaVbeta3 ({alpha}v{beta}3) peptide

14067 Background: In vivo imaging of avβ3 expression in tumors and tumor endothelial cells may be a useful biomarker of angiogenesis. [18F]AH11585 is a novel peptide containing an Arginine-Glycine-Aspartic Acid (RGD) motif that binds to avβ3 with high affinity designed for use in PET studies. Methods: 7 patients with metastatic breast cancer (aged 37–68 years) received intravenous injections of [18F]AH11585 and were scanned dynamically by PET over 61.5 mins. Radioactivity concentrations, derived from regions of interest placed on tumour and normal tissues, were analysed mathematically to determine the net irreversible uptake (Ki), fractional retention (FRT) and standardized uptake at 56.5min (SUV) of the radiotracer. Computed tomography (CT) was performed within 4 weeks of the scan. Results: Tumor lesions were clearly visible on PET images in 6/7 patients. In one patient with a palpable supraclavicular lymph node not visible on CT, we were unsure if a hyperintense region visible by PET was tumor. In total...