Department of Radiation Oncology, Medical Center - University of Freiburg, University of Freiburg, Freiburg, Germany.
German Cancer Consortium (DKTK), Partner Site DKTK-Freiburg, Freiburg, Germany.
Adv Exp Med Biol. 2024;1463:293-299. doi: 10.1007/978-3-031-67458-7_48.
Mild hyperthermia at 39-43 °C for 30-60 min is applied locoregionally to improve the oxygenation status of recurrent breast cancers, thus enhancing the efficacy of radio-, chemo-, and immunotherapy. In this context, estimated (or even conflicting) data are often used in computational modelling of tumour oxygenation and simulation of O transport. In this chapter, we present information that may help to improve adjuvant thermotherapy delivered immediately prior to radiotherapy of recurrent breast cancers. Data are preferentially derived from clinical investigations; in some cases, measurements in experimental breast cancers are included.The biophysical properties presented for healthy, mostly postmenopausal, human breast (composite glandular-adipose-fibrous tissue) measured under normothermic (NT) conditions and in therapeutically heated breast cancers include tissue water content and tissue density. In general, averaged values of parameters reported for NT conditions are higher in breast cancers than in normal breast tissue, i.e., all ratios breast cancer/normal breast are >1. Mean values observed in breast cancers during mild hyperthermia (mHT) are consistently higher than those in NT tumours. Parameters determining convective transports in healthy breast tissue and breast cancer include blood flow rates, blood volume, exchanging water space, arterio-venous shunt flow, interstitial fluid flow rate, interstitial fluid pressure, microvascular permeability, interstitial hydraulic conductivity, and interstitial flow velocity. In general, averaged values of parameters measured under NT conditions are higher in breast cancers than in healthy breast. Except for interstitial fluid pressure, these values increase upon mHT treatment of cancers. Prime factors determining and describing the oxygenation status of the healthy breast, and in NT- versus mHT-treated breast cancers, include: oxygen (O) delivery rates, O- extractions, O- consumption rates, subepidermal microvascular HbO, tissue oxygen solubility, oxygen diffusion coefficients, mean O partial pressures pO, hypoxic fractions HF <5 mmHg, oxygen enhancement ratio, and mitochondrial ROS production. With the exception of the mean pO, O extraction rate and tissue O saturation all parameters listed are distinctly higher in breast cancers under NT conditions compared to normal breast. Mild hyperthermia results in therapeutically relevant improvements of the oxygenation status of cancers and enhances mitochondrial ROS production, thus improving radiosensitivity. Note: The oxygenation status of the healthy (postmenopausal) breast is very similar to that of the normal human subcutis.
39-43°C 下 30-60 分钟的轻度热疗被局部应用于改善复发性乳腺癌的氧合状态，从而增强放射、化疗和免疫治疗的疗效。在这方面，计算肿瘤氧合建模和 O 传输模拟中经常使用估计的（甚至相互冲突的）数据。在这一章中，我们提供了一些信息，这些信息可能有助于改善复发性乳腺癌放射治疗前立即进行的辅助热疗。数据优先从临床研究中获得；在某些情况下，还包括实验性乳腺癌的测量。为正常（绝经后）人体乳房（复合腺体-脂肪-纤维组织）在常温（NT）条件下和治疗性加热的乳腺癌下呈现的生物物理特性包括组织含水量和组织密度。一般来说，在 NT 条件下报告的参数的平均值在乳腺癌中高于正常乳房组织，即所有乳腺癌/正常乳房的比值>1。在轻度热疗（mHT）期间观察到的乳腺癌的平均值始终高于 NT 肿瘤。在健康乳房组织和乳腺癌中决定对流传输的参数包括血流速率、血容量、交换水空间、动静脉分流流量、间质液流率、间质液压力、微血管通透性、间质水力传导率和间质流速。一般来说，在 NT 条件下测量的参数的平均值在乳腺癌中高于健康乳房。除了间质液压力外，这些值在癌症的 mHT 治疗下会增加。决定和描述健康乳房以及 NT-和 mHT-治疗的乳腺癌中的氧合状态的主要因素包括：氧（O）输送率、O 提取率、O 消耗率、表皮下微血管 HbO、组织氧溶解度、氧扩散系数、平均 O 分压 pO、低氧分数 HF<5mmHg、氧增强比和线粒体 ROS 产生。除了平均 pO 外，O 提取率和组织 O 饱和度在 NT 条件下所有列出的参数在乳腺癌中明显高于正常乳房。轻度热疗可显著改善癌症的氧合状态，并增强线粒体 ROS 产生，从而提高放射敏感性。注：健康（绝经后）乳房的氧合状态与正常人体皮下组织非常相似。
