Computer Modeling for Microwave Ablation in Breast Cancer Using a Coaxial Slot Antenna

Abstract

The use of breast cancer mammography screening has allowed detection of a greater number of small carcinomas, and this has facilitated treatment by minimally invasive techniques. Microwave energy is a promising alternative treatment because it can preferentially heat and damage high-water-content breast carcinomas. In order to evaluate the feasibility of using this technique to treat breast cancer, a coaxial slot antenna computer simulation based on an axisymmetric finite element method (FEM) model was used to compare heating differences between cancer and normal breast tissue. Three FEM computer models were developed: in one of them, the coaxial slot antenna was immersed only in homogeneous breast tissue; for the second one, the antenna was immersed only in cancer tissue; for the third one, the antenna was inserted into malignant tissue surrounded by breast tissue. According to the results, the computer modeling demonstrated that the difference in dielectric properties and thermal parameters between malignant and normal adipose-dominated tissue was able to cause preferential heating of tumors during microwave ablation. Furthermore, the ablation zone radius was 42 % larger in the tumor than in low-water-content adipose tissue. Even though this technique requires further research, it is a promising minimally invasive modality for the local treatment of breast cancer.