ELASTIC SCATTERING SPECTROSCOPY FOR NONINVASIVE DETECTION OF CANCER

Optical spectroscopy mediated by fibre-optic probes can be used to perform noninvasive, or minimally-invasive, real-time assessment of tissue pathology in-situ. The most common approaches have been based on UV-induced fluorescence spectroscopy and Raman spectroscopy, which are assumed to be responsive to biochemical changes in cells. On the other hand, our method of elastic-scattering spectroscopy (ESS) is sensitive to the sub-cellular architectural changes, such as nuclear grade or nuclear to cytoplasm ratio, mitochondrial size and density, etc., which correlate with features used in histological assessment. The ESS method senses those morphology changes in a semi-quantitative manner, without actually imaging the microscopic structure. To aid in the design of optical probes and the understanding of the resulting spectroscopic signals, modelling of photon scattering and migration in tissue is carried out using Mie theory and Monte Carlo simulations. Clinical demonstrations of ESS have been conducted in a variety of organ sites, and promising results have been obtained. Larger-scale clinical studies are now starting.