Wang Hang, Shi Xuetao, Cao Xinsheng, Dong Xiuzhen, Yang Lin
Department of Aerospace Medicine, Fourth Military Medical University, Xi'an, China.
Department of Biomedical Engineering, Fourth Military Medical University, Xi'an, China.
Front Physiol. 2023 Mar 17;14:1121599. doi: 10.3389/fphys.2023.1121599. eCollection 2023.
Renal cell carcinoma (RCC) poses a serious threat to human health, which urgently requires a method that can quickly distinguish between human normal renal tissue (NRT) and RCC for the purpose of accurate detection in clinical practice. The significant difference in cell morphology between NRT and RCC tissue underlies the great potential of the bioelectrical impedance analysis (BIA) to distinguish two types of human tissues. The study aims to achieve such discrimination through comparison of their dielectric properties within the frequency range from 10 Hz to 100 MHz. The dielectric properties of 69 cases of human normal and cancer renal tissue were measured 15 min after tissue isolation in a strictly controlled environment (37°C, 90% humidity). In addition to the impedance parameters (resistivity, conductivity and relative permittivity), the characteristic parameters extracted from the Cole curve were also compared between NRT and RCC. Furthermore, a novel index, distinguishing coefficient (DC), was used to obtain the optimal frequency for discrimination between NRT and RCC. In terms of impedance parameters, the RCC conductivity at low frequencies (<1 kHz) was about 1.4 times as large as that of NRT, and its relative permittivity was also significantly higher ( < 0.05). In terms of characteristic parameters, two characteristic frequencies (14.1 ± 1.1 kHz and 1.16 ± 0.13 MHz) were found for NRT while only one for RCC (0.60 ± 0.05 MHz). A significant difference of low-frequency resistance (R) between RCC and NRT was also observed ( < 0.05). As for the new index DC, relative permittivity DCs below 100 Hz and at around 14 kHz were both greater than 1. These findings further confirm the feasibility of discrimination between RCC and NRT and also provide data in favor of further clinical study of BIA to detect the surgical margins.
肾细胞癌（RCC）对人类健康构成严重威胁，临床实践中迫切需要一种能够快速区分人类正常肾组织（NRT）和RCC的方法，以实现准确检测。NRT和RCC组织之间细胞形态的显著差异使得生物电阻抗分析（BIA）在区分这两种人类组织方面具有巨大潜力。本研究旨在通过比较它们在10 Hz至100 MHz频率范围内的介电特性来实现这种区分。在严格控制的环境（37°C，90%湿度）中，组织分离15分钟后测量了69例人类正常和癌性肾组织的介电特性。除了阻抗参数（电阻率、电导率和相对介电常数）外，还比较了NRT和RCC之间从科尔曲线提取的特征参数。此外，还使用了一种新的指标——区分系数（DC）来获得区分NRT和RCC的最佳频率。在阻抗参数方面，低频（<1 kHz）下RCC的电导率约为NRT的1.4倍，其相对介电常数也显著更高（<0.05）。在特征参数方面，发现NRT有两个特征频率（14.1±1.1 kHz和1.16±0.13 MHz），而RCC只有一个（0.60±0.05 MHz）。还观察到RCC和NRT之间低频电阻（R）存在显著差异（<0.05）。至于新指标DC，低于100 Hz和14 kHz左右的相对介电常数DC均大于1。这些发现进一步证实了区分RCC和NRT的可行性，也为BIA检测手术切缘的进一步临床研究提供了数据支持。
