Despite considerable progress in, and impressive effectiveness of various non-invasive cancer treatments such as radiotherapy (RT) and chemotherapy (ChT), the clinical outcomes are somewhat variable because of the variation in individual patient responses. If some convenient measurements from specific patients undergoing specific treatments could be made that report on treatment progress and response, these could be used to select responders from non-responders, alter ‘the doses’ for the remaining treatment, and in general optimize the therapies based on individual treatment feedback.
A promising novel imaging technique for detecting early treatment responses in vivo is based on photonic technologies and is called optical coherence tomography (OCT). OCT is essentially an optical analog of ultrasound but uses near-infrared electromagnetic waves rather than mechanical sound waves. Microscopy-like subsurface images of tissue microstructure and microvasculature are possible with OCT in living tissues. For this project, we are developing the enabling OCT imaging technologies and conducting preclinical and selected clinical studies to come up with quantifiable metrics of tumour and normal tissue responses to a variety of minimally invasive therapies.
Specifically, the OCT imaging platform is being expended / refined to enable multiple modes of operation, including direct structural, polarization-sensitive, angiographic, and elastographic regimes. These will yield unique high-resolution imaging information on tissue cellular organization, connective tissue compartment, blood microcirculation, and tissue hardness / stiffness, respectively. The ability of these multiple important and complimentary information channels to detect treatment induced changes will be tested preclinically in a series of normal and tumour-bearing mice undergoing ChT, RT, and also photodynamic therapy (PDT). A series of treatment-specific multi-modal OCT response metrics will be derived, and then tested in a series of further clinical pilot studies of PDT, RT and ChT in the oral cavity, skin, lower GI tract, and cervix of patients with cancers in these clinical sites. Initial results of this research will be highlighted in this presentation. It is hoped that the multimodal OCT technologies and treatment response metrics thus developed will help usher in the era of “personalized cancer medicine” of the 21st century.