Differential Evolution Optimization of the SAR Distribution for Head and Neck Hyperthermia

Area of Science:

• Oncology
• Biomedical Engineering
• Medical Physics

Background:

• Hyperthermia uses heat for cancer treatment, often with electromagnetic energy.
• Effective hyperthermia treatment planning (HTP) requires precise energy focusing to target tumors and avoid healthy tissues.

Purpose of the Study:

• To present a novel method for optimizing specific absorption rate (SAR) distribution in head and neck cancer hyperthermia.
• To improve microwave energy focusing into the tumor and minimize hot spots in surrounding healthy tissues.

Main Methods:

• A differential evolution (DE) optimization algorithm was developed to enhance SAR distribution.
• The DE algorithm was tested using the Erasmus MC patient dataset and compared with particle swarm optimization (PSO).
• Performance was evaluated using clinical metrics like hot-spot-tumor SAR quotient (HTQ) and temperature parameters.

Main Results:

• The DE algorithm demonstrated improved focusing of microwave energy absorption to the target region.
• DE significantly outperformed the PSO algorithm, currently used in clinics.
• DE showed a 40.1-96.8% improvement in HTQ standard deviation across six patients.

Conclusions:

• Differential evolution (DE) offers a superior approach for optimizing SAR distribution in head and neck cancer hyperthermia.
• DE enhances treatment efficacy by improving energy deposition accuracy and reducing thermal damage to healthy tissues.
• This method holds promise for more effective and safer hyperthermia cancer treatments.