Vaupel P, Kelleher D K, Thews O
Institute of Physiology and Pathophysiology, University of Mainz, Germany.
Int J Radiat Oncol Biol Phys. 1998 Nov 1;42(4):843-8. doi: 10.1016/s0360-3016(98)00324-1.
There is a large body of evidence suggesting that deficiencies in the O2 supply of tumors exist due to restrictions (i) in the O2 delivery by perfusion and/or diffusion, and (ii) in the O2 transport capacity. Whereas the former are mostly based on inadequate and heterogeneous microcirculatory functions, the latter are predominantly due to tumor-associated anemia. Possible uses and limitations of measures are discussed which can increase the microvascular O2 content and thus may preferentially serve to enhance diffusion-limited O2 availability. In addition, means are described for improving and increasing the uniformity of microcirculation thus possibly enhancing perfusion-limited O2 delivery. Reducing cellular respiration rate should be of benefit in both pathophysiological conditions. Because both types of O2 limitation coexist in solid tumors, appropriate combinations should be aimed at eradicating tumor hypoxia which is present in at least one third of cancers in the clinical setting.
大量证据表明，肿瘤存在氧气供应不足的情况，这是由于以下两方面的限制：（i）灌注和/或扩散导致的氧气输送受限，以及（ii）氧气运输能力受限。前者主要基于不充分且不均匀的微循环功能，后者主要归因于肿瘤相关性贫血。本文讨论了一些措施的可能用途和局限性，这些措施可增加微血管中的氧气含量，从而可能优先用于提高扩散受限的氧气供应。此外，还描述了改善和提高微循环均匀性的方法，从而可能增强灌注受限的氧气输送。降低细胞呼吸速率在这两种病理生理状况下都应是有益的。由于实体瘤中这两种氧气限制并存，应采用适当的组合方式以消除肿瘤缺氧，临床环境中至少三分之一的癌症存在肿瘤缺氧情况。
