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 ‘nominal-the-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.

中文翻译：

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纳米粒子介导的热疗肿瘤消融体积的优化

摘要 用于治疗性肿瘤特异性加热的纳米粒子辅助热疗法正在成为一种有前途的、微创的未来癌症治疗方法。为了在对健康组织损伤最小的情况下有效消融肿瘤，必须先验优化控制因素。在这项研究中，包括肿瘤直径从 1 cm 到 3 cm 的二维组织域用于优化肿瘤消融体积的控制因素。特别是，辐照度、辐照持续时间和粒子体积分数发生变化以优化热损伤（即根据 Arrhenius 方程结合 Pennes 的生物热模型计算）。Taguchi 的全因子方法与 L27 正交阵列一起用于控制因子。实施“标称最佳”方法以针对每个肿瘤大小的最佳消融体积。结果表明，烧蚀体积从 0.75 W/cm2 的辐照度水平增加到 1.50 W/cm2，照射持续时间为 70-80 s 到 120-130 s，颗粒体积分数从 0.00001% 增加到 0.0001%（即每个参数从低到高水平）每个肿瘤大小。还发现这些控制因素对于较大的肿瘤直径显示出最高的梯度。在控制因素中，辐照度成为重要因素，对肿瘤消融量有显着影响。最终，研究表明，这种方法可用于定义一组精确的控制因素（特定于每个肿瘤大小），以达到最小变化的目标消融体积，