Routes to Optimizing Photothermal Cancer Therapy through a Comprehensive Theoretical Model

Nanoparticle-assisted photothermal therapy is a soft tissue ablation method where nanoparticles embedded in tissue absorb near-infrared light, converting it to heat and raising temperatures directly where the nanoparticles are located, with minimal damage to adjacent tissue. Developing a method that accurately predicts light and heat dissipation within both pristine and nanoparticle-embedded tissues is essential for making this process as efficient as possible. Here, we report a theoretical model of nanoparticle-assisted photothermal therapy that provides a deeper understanding of this process. The model considers light scattering and absorption by tissue and nanoparticles, resulting in heat generation and dissipation. We find that the thermal response is a consequence of two competing processes, increased light absorption and backscattering, both dependent on nanoparticle concentration, and we accurately account for temperature-dependent tissue properties. Through this approach, we found that spatial and temporal modulation of the laser intensity, combined with heat localization, can dramatically increase the efficiency of the ablation process, resulting in a 44% greater ablation volume in 33% less illumination time. Our critical examination of this therapeutic approach through a robust, data-validated model offers valuable insights into practical strategies for potentially game-changing treatment optimization.