Characterizing Normal and Tumour Blood Microcirculatory Systems Using Optical Coherence Tomography

Blood vessels transport blood and deliver essential molecules to cells. In cancer, the tumour vasculature evolves very differently from healthy tissue, not only in morphology but also in functionality. Comprehensive 3D in vivo imaging of the tumour microcirculatory system thus might lead to a clearer understanding of the vascular role in tumour growth and response to cancer therapy. Here, we employed two optical coherence tomography (OCT) extensions, speckle-variance and Doppler, to study the microvascular architecture and blood flow in normal murine and xenograft tumour tissue. We explored the biophysics of blood flow in microcirculation and extracted relevant quantification features such as vessel diameters and velocity histograms, and combined diameter–velocity plots. It was demonstrated that tumour microcirculation evolves in time and differs from healthy tissue, impacting tumour growth kinetics. This proof-of-principle study demonstrates the potential of OCT to provide an understanding of the temporal evolution of the tumour vasculature and its relationship with tumour development.