Prasad Kedar N
Center for Vitamin and Cancer Research, Department of Radiology, University of Colorado Health Sciences Center, Denver 80262-0278, USA.
Integr Cancer Ther. 2004 Dec;3(4):310-22. doi: 10.1177/1534735404270936.
Cancer patients can be divided into 3 groups: those receiving standard or experimental therapy, those who have become unresponsive to these therapies, and those in remission at risk for recurrence or a second new cancer. While impressive progress in standard cancer therapy has been made, the value of this therapy in the management of solid tumors may have reached a plateau. At present, there is no strategy to reduce the risk of recurrence of the primary tumors or of a second cancer among survivors. Patients unresponsive to standard or experimental therapies have little option except for poor quality of life for the remainder of life. Therefore, additional approaches should be developed to improve the efficacy of current management of cancer. In this review, the author proposes that an active nutritional protocol that includes high doses of multiple dietary antioxidants and their derivatives (vitamin C, alpha-tocopheryl succinate, and natural beta-carotene), but not endogenously made antioxidants (glutathione- and antioxidant enzyme-elevating agents), when administered as an adjunct to radiation therapy, chemotherapy, or experimental therapy, may improve its efficacy by increasing tumor response and decreasing toxicity. This nutritional protocol can also be used when patients become unresponsive to standard therapy or experimental therapy to improve quality of life and possibly increase the survival time. The authors also propose that after completion of standard therapy and/or experimental therapy, a maintenance nutritional protocol that contains lower doses of antioxidants and their derivatives, together with modification in diet and lifestyle, may reduce the risk of recurrence of the original tumor and development of a second cancer among survivors. Experimental data and limited human studies suggest that use of these nutritional approaches may improve oncologic outcomes and decrease toxicity. This review also discusses the reasons for the current debates regarding the use of antioxidants during radiation or chemotherapy.
癌症患者可分为3组：接受标准治疗或实验性治疗的患者；对这些治疗无反应的患者；处于缓解期但有复发风险或患第二种新发癌症风险的患者。虽然标准癌症治疗已取得显著进展，但这种治疗在实体瘤管理中的价值可能已达到平台期。目前，尚无策略可降低幸存者中原发性肿瘤复发或患第二种癌症的风险。对标准或实验性治疗无反应的患者除了余生生活质量较差外别无选择。因此，应开发其他方法来提高当前癌症管理的疗效。在本综述中，作者提出，一种积极的营养方案，包括高剂量的多种膳食抗氧化剂及其衍生物（维生素C、琥珀酸生育酚和天然β-胡萝卜素），但不包括内源性产生的抗氧化剂（提高谷胱甘肽和抗氧化酶的药物），在作为放射治疗、化疗或实验性治疗的辅助手段使用时，可能通过增加肿瘤反应和降低毒性来提高其疗效。当患者对标准治疗或实验性治疗无反应时，也可使用这种营养方案来改善生活质量并可能延长生存时间。作者还提出，在完成标准治疗和/或实验性治疗后，一种维持性营养方案，包含较低剂量的抗氧化剂及其衍生物，同时改变饮食和生活方式，可能降低幸存者中原发性肿瘤复发和患第二种癌症的风险。实验数据和有限的人体研究表明，使用这些营养方法可能改善肿瘤治疗结果并降低毒性。本综述还讨论了当前关于在放疗或化疗期间使用抗氧化剂的争论的原因。
