Sidestream dark field videomicroscopy for in vivo evaluation of vascularization and perfusion of mammary tumours in HER 2/neu transgenic mice

Summary Angiogenesis plays a key role in tumour growth and the formation of metastases. Angiogenesis inhibitors and antivascular agents may prove useful in the treatment of breast cancer. A comprehensive characterization of the vasculature and perfusion of mammary tumours is a prerequisite for developing new specific drugs. We used sidestream dark field videomicroscopy to evaluate in vivo the vascular network of spontaneous mammary tumours in HER 2/neu transgenic mice. The tumour masses showed higher vessel density compared with the healthy mammary gland (median (interquartile range) total vessel density 16.8 (13.4–20.5) vs 9.1 (8.1–10.9) mm/mm 2 , respectively; P  < 0.001). Tumor vessel density was reduced in mice treated with the anti‐angiogenesis agent berberine, 12.1 (10.6–13.1) mm/mm 2 . Sidestream dark field imaging is a versatile technique that may be useful for understanding the role of angiogenesis in the progression of breast cancer and its relationship with outcome. It may represent a valuable tool for dynamic monitoring of the effects of new anti‐angiogenesis therapies.