Thermo-Dielectric Breast Phantom for Experimental Studies of Microwave Hyperthermia

An artificial breast phantom that has realistic dielectric and thermal properties is presented. The phantom aims at enabling the experimental validation of microwave hyperthermia treatment for breast cancer. To perform credible breast hyperthermia experiments, the phantom should emulate both of the dielectric (permittivity and conductivity) and thermal properties (specific heat capacity and thermal conductivity) of different breast tissues with the correct anatomy. The main challenge in fabricating such a phantom is in developing suitable mixtures of materials to emulate those properties across the frequency band of interest in hyperthermia and to fabricate the phantom with realistic anatomy. For anatomical accuracy, a patient-specific MRI model is utilized in a three-dimensional printer, which is used to cast molds of the different breast tissues. Those molds are then filled with tissue-mimicking chemicals, which are formed using low cost and stable materials. Once fabricated, the dielectric properties are measured using a dielectric probe, while the thermal properties are measured using a differential scanning calorimeter. Our measurements confirm the suitability of the fabricated breast phantom across the band 3-5 GHz, which is the suitable band for microwave hyperthermia.