Experimental and numerical analysis of a capacitive hyperthermia device

Capacitive hyperthermia is a promising adjuvant cancer treatment, but its efficacy strongly depends on tissue properties and device operating conditions. Therefore, reliable simulation frameworks are pivotal to support treatment planning and optimization. To this end, this study investigates the electro-thermal performance of the HY-DEEP 600WM capacitive hyperthermia device, developing a new Multiphysics numerical model, and validating it on experimental data. The model is solved by coupling the electro-quasistatic current-conservation equation together with Pennes' bioheat equation, accounting for realistic electrode geometry, material properties, cooling conditions, and transient heat transfer. Experimental validation was performed on an agarose phantom exposed at 550 W for 30 min with 77% duty cycle, proving the model's reliability, with maximum temperature differences below 1.5 °C and maximum mean absolute error of 0.73 °C. The validated model was then applied to two parametric studies, to provide useful guidelines for clinicians to assess treatment efficacy for different tissue stratigraphy. In the soft-tissue configuration, increasing adipose thickness promoted superficial heating and reduced deep thermal penetration. In the leanest case (0.5 cm fat, 14 cm muscle), a nearly uniform intramuscular temperature within the therapeutic range of 42–43 °C was achieved, whereas thicker adipose layers caused surface hot spots (up to 50 °C) and lower deep-tissue temperatures (39 °C, below the hyperthermic temperatures). In the cranial configuration, the skull acted as a shielding layer; at 300 W, intracranial temperatures remained below 42 °C in all cases. These results confirm that heat penetration in capacitive deep hyperthermia depends on tissue characteristics and thickness.