Abstract

Hyperthermia treatment planning (HTP) is valuable to optimize tumor heating during thermal therapy delivery. Yet, clinical hyperthermia treatment plans lack quantitative accuracy due to uncertainties in tissue properties and modeling, and report tumor absorbed power and temperature distributions which cannot be linked directly to treatment outcome. Over the last decade, considerable progress has been made to address these inaccuracies and therefore improve the reliability of hyperthermia treatment planning. Patient-specific electrical tissue conductivity derived from MR measurements has been introduced to accurately model the power deposition in the patient. Thermodynamic fluid modeling has been developed to account for the convective heat transport in fluids such as urine in the bladder. Moreover, discrete vasculature trees have been included in thermal models to account for the impact of thermally significant large blood vessels. Computationally efficient optimization strategies based on SAR and temperature distributions have been established to calculate the phase-amplitude settings that provide the best tumor thermal dose while avoiding hot spots in normal tissue. Finally, biological modeling has been developed to quantify the hyperthermic radiosensitization effect in terms of equivalent radiation dose of the combined radiotherapy and hyperthermia treatment. In this paper, we review the present status of these developments and illustrate the most relevant advanced elements within a single treatment planning example of a cervical cancer patient. The resulting advanced HTP workflow paves the way for a clinically feasible and more reliable patient-specific hyperthermia treatment planning.

摘要

热疗治疗计划（HTP）对于优化热疗过程中的肿瘤加热非常有价值。然而，由于组织特性和模型的不确定性，临床热疗治疗计划缺乏定量准确性，并且报告了肿瘤吸收能力和温度分布，而这不能直接与治疗结果相关。在过去的十年中，在解决这些不准确方面已经取得了相当大的进步，因此提高了热疗治疗计划的可靠性。已经引入了从MR测量得出的特定于患者的组织电导率，以准确地模拟患者体内的功率沉积。已经开发出热力学流体模型以解决诸如膀胱中的尿液之类的对流热传递。此外，离散的脉管系统树已包含在热模型中，以说明重要的热大血管的影响。已经建立了基于SAR和温度分布的计算有效的优化策略，以计算可提供最佳肿瘤热剂量并避免正常组织出现热点的相幅设置。最后，已经开发了生物学模型以根据联合放射疗法和高温疗法的等效放射剂量来量化高温放射致敏作用。在本文中，我们回顾了这些进展的现状，并举例说明了子宫颈癌患者的单一治疗计划实例中最相关的先进要素。