Towards thermal differential imaging for ultra-wideband microwave breast cancer detection

Microwaves can be employed for biomedical applications, e.g. breast cancer detection, to generate physically independent information about the biological tissue compared to conventional techniques such as X-ray, ultrasound or MRI. One challenge to increase the sensitivity of microwave diagnostics is the elimination of the high amplitude reflection that occurs at the skin surface and which masks the small amplitude reflections coming from the tumour. In this paper, we will present a novel approach for contrast enhanced microwave imaging of the breast where the temperature dependency of the biological tissue is used together with its ability to heat biological tissue. A dielectric contrast has been observed at a small temperature increase of about 1°C, similar to fever, which is enough to extract the scattering response of the tumour.