Harrison Louis B, Shasha Daniel, Homel Peter
Department of Radiation Oncology, Beth Israel Medical Center/St Luke's-Roosevelt Hospital Center, New York, N.Y. 10003, USA.
Oncology. 2002;63 Suppl 2:11-8. doi: 10.1159/000067147.
As the antitumor activity of radiation is mediated via its interaction with oxygen to form labile free radicals, the intratumoral oxygen level has an important influence on the ability of radiation therapy to kill malignant cells. By decreasing the oxygen-carrying capacity of the blood, anemia may result in tumor hypoxia and may have a negative influence on the outcome of radiotherapy for various malignancies, even for small tumors not normally assumed to be hypoxic. In addition, anemia also has a negative effect on the quality of life of cancer patients, as evidenced by worsening fatigue. As a high proportion (about 50%) of cancer patients undergoing radiotherapy are anemic prior to or during treatment, strategies to correct anemia and/or the resultant tumor hypoxia are increasingly being considered an important component of treatment. In particular, epoetin alfa (recombinant human erythropoietin), which has proved an effective and well-tolerated means of raising hemoglobin levels in anemic patients receiving radiotherapy, potentially could reverse the negative prognostic influence of a low hemoglobin in patients with certain malignancies. Radiation oncologists need to be aware of the possibility of anemia in cancer patients undergoing radiotherapy so that timely intervention can be instituted whenever anemia is diagnosed.
由于辐射的抗肿瘤活性是通过其与氧相互作用形成不稳定自由基来介导的，肿瘤内的氧水平对放射治疗杀死恶性细胞的能力有重要影响。贫血会降低血液的携氧能力，可能导致肿瘤缺氧，并可能对各种恶性肿瘤的放射治疗结果产生负面影响，即使是对于通常不认为会缺氧的小肿瘤也是如此。此外，贫血对癌症患者的生活质量也有负面影响，疲劳加剧就证明了这一点。由于接受放射治疗的癌症患者中有很大比例（约50%）在治疗前或治疗期间贫血，纠正贫血和/或由此导致的肿瘤缺氧的策略越来越被视为治疗的重要组成部分。特别是，促红细胞生成素α（重组人促红细胞生成素）已被证明是提高接受放射治疗的贫血患者血红蛋白水平的一种有效且耐受性良好的方法，它有可能扭转某些恶性肿瘤患者低血红蛋白的负面预后影响。放射肿瘤学家需要意识到接受放射治疗的癌症患者出现贫血的可能性，以便在诊断出贫血时能够及时进行干预。
