Braichotte D, Savary J F, Glanzmann T, Westermann P, Folli S, Wagnieres G, Monnier P, Van den Bergh H
Institut de Génie de l'Environnement, Ecole Polytechnique Fédérale, Lausanne, Switzerland.
Int J Cancer. 1995 Oct 9;63(2):198-204. doi: 10.1002/ijc.2910630209.
To optimize photodynamic therapy (PDT) and photodetection of cancer with second-generation photosensitizers, knowledge of important variables such as the uptake of the dye and the dye contrast between normal and tumoral tissue after injection is necessary. The pharmacokinetics of a second-generation photosensitizer, tetra(meta-hydroxyphenyl)chlorin (mTHPC), is presented. To study this in a clinical context, an apparatus based on fluorescence spectroscopy and a noninvasive optical fiber probe has been used. The mTHPC fluorescence is induced at 2 excitation wavelengths (420 and 520 nm) with different penetration depth. The pharmacokinetics of mTHPC in patients with a squamous-cell carcinoma in the oral cavity show a signal selectivity as high as 16 about 3 hr after i.v. injection for the more advanced carcinomas. The magnitude of this selectivity appears to correlate with the staging of the cancer, the more invasive tumors showing the highest selectivity. Results obtained at 420 and 520 nm show little difference. These pharmacokinetics can be used directly for optimizing photodetection with mTHPC. However, complementary information on the localization of the drug by fluorescence microscopy, and a correlation of this data with tumor necrosis efficacy, are needed to optimize PDT timing.
为了利用第二代光敏剂优化光动力疗法（PDT）和癌症的光检测，了解诸如染料摄取以及注射后正常组织与肿瘤组织之间的染料对比度等重要变量是必要的。本文介绍了第二代光敏剂四（间羟基苯基）氯卟啉（mTHPC）的药代动力学。为了在临床环境中对此进行研究，使用了一种基于荧光光谱和无创光纤探头的设备。mTHPC荧光在具有不同穿透深度的2个激发波长（420和520 nm）下诱导产生。口腔鳞状细胞癌患者体内mTHPC的药代动力学显示，对于更晚期的癌症，静脉注射后约3小时信号选择性高达16。这种选择性的大小似乎与癌症分期相关，侵袭性越强的肿瘤显示出的选择性越高。在420和520 nm处获得的结果差异不大。这些药代动力学可直接用于优化mTHPC的光检测。然而，需要通过荧光显微镜获得关于药物定位的补充信息，以及这些数据与肿瘤坏死疗效的相关性，以优化PDT的时机。
