Advancing Microwave Hyperthermia for breast cancer treatment using Nanoparticles

Researchers from the Electromagnetics Research Group (EMRG) within the Department of Physics have developed and numerically validated an enhanced microwave hyperthermia approach for breast cancer treatment using gold nanoparticles and advanced electromagnetic optimisation techniques.

The study, carried out in collaboration with international partners from Istanbul Technical University and University College London (UCL), investigates how gold nanoparticles can improve the localisation of microwave energy within tumour tissue, potentially enabling more effective and targeted hyperthermia treatments.

Microwave hyperthermia is an emerging adjunct cancer therapy in which tumour tissues are heated to therapeutic temperatures between 40 °C and 45 °C, making cancer cells more vulnerable to chemotherapy and radiotherapy while minimising damage to surrounding healthy tissues.

The research utilised an innovative eight-element Fractal Octagonal Ring Antenna (FORA) array operating at 2.45 GHz to focus electromagnetic energy into a three-dimensional breast phantom model containing an embedded tumour. Advanced optimisation methods were implemented both directly within CST Microwave Studio and through a dedicated Python-based framework developed in-house.

The results demonstrated that introducing peptide-capped gold nanoparticles within the tumour region significantly enhanced microwave energy absorption. Numerical simulations showed a 65–75% increase in peak specific absorption rate (SAR), alongside substantial improvements in tumour-selective energy focusing without introducing additional hotspots in surrounding healthy tissue.

Importantly, the Python-based optimisation approach achieved similar focusing performance while reducing computational time by approximately six- to seven-fold compared to full direct electromagnetic optimisation methods. This provides an important step toward rapid treatment planning and patient-specific optimisation strategies for microwave hyperthermia systems.

The work also highlights the growing importance of combining electromagnetic engineering, thermal modelling, and nanotechnology in biomedical applications. Gold nanoparticles were synthesised and characterised in collaboration with UCL researchers, while their dielectric behaviour was experimentally measured and incorporated into the numerical models.

This research forms part of the EMRG’s broader efforts in advancing microwave-based biomedical technologies and contributes toward the long-term goal of developing safer, more effective, and clinically translatable hyperthermia technologies for cancer treatment.

This work is part of the project "Hyper4B" funded by Xjenza Malta - TUBITAK Joint Call for R&I Proposals 2023.