Microwave Hyperthermia: Enhancing the Conventional Breast Cancer Treatments with Thermal Therapies

2017 edition

Aleix Garcia

Breast cancer is the most relevant cancer among women worlwide. The impact of the breast cancer in our society is such that in 2012 breast cancer represented, among Spanish women, the 29% of the new diagnosed tumors, with a death rate of 15.5% and a prevalence in 5 years of 40.8%. To reverse this situation, new research is leading to the development of complementary minimally-invasive therapies for the improvement of the conventional treatments carried out with chemotherapy or radiotherapy. In that sense, thermal therapy arises as a new approach to improve such treatments. It has been demonstrated that hyperthermia, a form of moderate thermal therapy involving heating the tumor tissue to temperatures in the range of 41 to 45 ┬░C, increases the effectiveness of chemotherapy and radiotherapy.

 

Current hyperthermia applicators for the breast cancer treatments are scarce, bulky, expensive and do not conform to the patient anatomy. Compact and wearable devices for delivering hyperthermia to breast targets are under development in order to improve patient comfort and system performance.

 

This study presents a low-cost wearable antenna array for delivering microwave hyperthermia to tumors located at varying locations within the breast. A focusing algorithm has been developed to maximize the specific absorption rate (SAR) in the tumor while maintain the healthy tissues in a safe temperature. Power constraints have also taken into account to optimize the system and the computational time. Canonical models and anatomically-representative computational phantoms were employed to assess SAR and thermal profiles. Experimental thermal validation on a preliminary prototype indicates practical feasibility of the system.