营养不良在恶性肿瘤患者中的发生率高达40%~80%，约有97% 的患者需要营养治疗。肿瘤相关的营养不良主 要由肿瘤的局部效应、机体对肿瘤的反应和抗肿瘤治疗引起。约70% 的肿瘤患者在肿瘤治疗过程中采用放射治疗，但在患 者放射治疗过程中和治疗后伴随的多种急性和慢性反应，容易导致患者营养不良，引起治疗中断或延迟，影响肿瘤患者的 生活质量和治疗效果，进而对预后产生不利影响。营养治疗可帮助放疗患者度过不良反应期、降低放疗引起的毒性反应、 改善患者机体状况、降低治疗不良事件的发生。因此应加强对患者放疗过程中和放疗后科学全面地评估营养状况，并尽早 进行个体化的营养指导和营养治疗，改善患者的营养状况和生存质量并协助抗肿瘤治疗的进行、降低肿瘤进展风险、改善 患者预后。本文总结了放射治疗对机体产生的不良反应和诱发的营养不良问题，以及营养不良状况对患者放疗效应、身体 状况的影响，通过回顾营养治疗在放疗患者中的应用，表明营养治疗对改善放疗患者生活质量和预后发挥重要作用。

Malnutrition was prevalent in cancer patients with incidence ranging from 40% to 80%. About 97% of the patients needed nutritional therapy. Malnutrition in oncology patients might be caused by multiple factors, including the psychological changes of tumor, response to the tumor and cancer treatment. About 70% of tumor patients prescribed radiotherapy in the course of therapy. However several acute and chronic responses accompany during and after the radiotherapy, which might easily lead to malnutrition in patients and cause therapy interruption and delay. This could have an impact on the quality of the patients’ lives and the therapeutic effect, having adverse effects on prognosis. Nutritional therapy could help radiotherapy patients pass through adverse reaction stage, reduce the toxic reaction caused by radiotherapy, improve phycical condition and reduce the occurrence of adverse events. Therefore, we should reinforce the nutritional status assessment during and after the radiotherapy scientifically and comprehensively and give individual nutritional therapy as early as possible. These might improve the nutritional status and quality of life of patients, which could not only help anticancer therapy, but also reduce the risks of tumor progression and improve the outcomes. This article summarized the malnutrition problems resulting from radiotherapy to the body and the influence of nutritional therapy on radiotherapy effect and physical condition of patients. The article suggested nutritional therapy plays an important role in improving quality of life and prognosis of patients by reviewing the application of nutritional therapy in patients with radiotherapy.