Abstract:
Nanoparticle-assisted thermal therapy for therapeutic tumor specific heating is emerging as a promising,
minimally-invasive future cancer treatment. For efficient ablation of a tumor with minimum damage to the
healthy tissue, the controlling factors must be optimized a-priori. In this study, a two dimensional tissue domain,
comprising tumor diameters from 1 cm to 3 cm, were used to optimize the controlling factors of tumor ablation
volume. In particular, irradiance, irradiation duration and particle volume fraction were varied to optimize the
thermal damage (i.e. calculated from the Arrhenius equation in combination with Pennes’ bioheat model).
Taguchi’s full factorial approach was used with an L27 orthogonal array for the controlling factors. The ‘nominalthe-
best’ approach was implemented to target the optimal ablation volume for each tumor size. The results show
that ablation volume increases from irradiance level of 0.75 W/cm2 to 1.50 W/cm2, irradiation duration of
70–80 s to 120–130 s and from a particle volume fraction of 0.00001% to a volume fraction of 0.0001% (i.e. from
low to high levels for each parameters) for each tumor size. It was also found that these controlling factors
showed the highest gradients for larger tumor diameters. Among the controlling factors, irradiance emerges as
the significant factor, with a pronounced effect on tumor ablation volume. Ultimately, the study shows that this
approach can be used to define a precise set of controlling factors (specific for each tumor size) to achieve the
target ablation volume with minimum variation, resulting in an efficient thermal therapy.
