Hydrogel and scalp/skin conductivities impact dose from tumor treating fields

Area of Science:

• Biophysics
• Medical Physics
• Oncology

Background:

• Tumor Treating Fields (TTFields) utilize electrical fields for cancer treatment.
• Dermatologic complications are associated with TTFields, potentially due to hydrogel and field intensity.
• Understanding conductivity's role is crucial for optimizing TTFields efficacy and safety.

Purpose of the Study:

• To investigate the impact of hydrogel and skin conductivity on TTFields penetration and coverage.
• To explore methods for improving TTFields distribution within tumor volumes.
• To mitigate dermatologic side effects associated with TTFields therapy.

Main Methods:

• Utilized MRI and PET-CT datasets to create finite element mesh models of patients.
• Simulated electric field distribution, energy deposition, and current density.
• Analyzed field coverage and hotspot metrics at varying hydrogel and skin conductivities.

Main Results:

• TTFields coverage at the gross tumor volume (GTV) and clinical target volume (CTV) plateaued around 0.5-1.0 S/m conductivity.
• Altering scalp conductivity significantly impacted TTFields distribution and skin hotspots.
• Optimizing conductivity showed potential for increased GTV coverage and reduced GTV hotspots.

Conclusions:

• Hydrogel and scalp/skin conductivity are key modulators of TTFields delivery.
• Optimizing interface conductivity can enhance tumor control and minimize skin toxicity.
• Further research into conductivity optimization holds promise for improving TTFields therapy outcomes.