Preliminary Study of 89 Zr Labeled Bevacizumab to Detect Angiogenesis in a Pre-Clinical Model of Sarcoma

The goal of the investigation was to demonstrate uptake of 89Zr labeled bevacizumab as non-invasive probe for angiogenesis in a xenograft model of sarcoma. Methods: HT-1080 human fibrosarcoma cell were established as xenografts in both athymic nude mice and BALB/c nude mice. Bevacizumab (Bev) was conjugated to 89 Zr oxalate using the bifunctional chelate, p-isothiocyanatobenzyl-desferrioxamine (Df-Bz-NCS). Mice were injected with1.8 – 3.7 MBq of 89 Zr-Bev and imaged over 11 days. Results: Uptake of 89 Zr-Bev was clearly demonstrated in HT-1080 xenografts with peak tumor SUVMAX at 4 days post injection when normal tissue uptake had reduced. Declining levels of radioactivity persisted in the tumor for the 11-day observation period. Significant uptake was seen in bone tissue. Conclusions: These preliminary results demonstrate that 89Zr-Bev is a potential new tracer for noninvasive imaging of VEGF in the microenvironment of sarcomas.