Combined ultrasound and light backscattering spectroscopy for cancer characterization: a proof of concept

Changes in the tissue microstructure occur at the cellular and nuclear scales when a tissue turns malignant. With the aim of assessing these alterations in a quantitative fashion, an ultrasound and a light backscattering technique have been combined to extract the scatterer size distribution from three different tissue-mimicking phantoms (diameter of 10 µ, 20 µm and 60 µm). The light-based technique showed more potential to characterize the 60 µm phantom (agreement with expected model R2 = 0.94) than the ultrasound-based method, which in turn better models and discriminates the 10 µm and the 20 µm phantom (R2 = 0.93 and R2 = 0.84 respectively). Results suggest that the two modalities could have complementary sensitivities regarding the scatterer sizes. The bimodal technique could potentially probe tumor microstructures at various scales, thereby allowing a thorough tissue characterization.