[Nutrition and cancer patients]

Nutritional therapy for cancer patients includes various objectives such as improvement of cachexia, elucidation of the mechanism of malnutrition, development of therapy for anorexia, nutrition support during chemotherapy or radiotherapy, and inhibition of tumor growth under controlled caloric intake. This review describes recent remarkable developments in nutritional therapy for cancer patients. Cytokines such as interleukin (IL)-1, IL-6, and tumor necrosis factor which induce proteolysis and lipolysis are involved in the cause of malnutrition and cachexia in cancer patients. IL-1 also plays a significant role in the development of cancer anorexia via direct action in the brain. For anorexia therapy, progestogens have been shown to improve appetite and food intake in cancer patients. Moreover, glutamine supplementation improves the host protein metabolism without enhancement of tumor growth during chemotherapy. Among the effects of caloric intake on anticancer therapy, AO-90, a methionine-free intravenous amino acid solution, has been shown to increase the antitumor effect of 5-fluorouracil in clinical studies. From these observations, recent progress in nutritional therapy for cancer patients has been remarkable. Further study of nutritional therapy is required in order to maintain or improve the quality of life of cancer patients in the future.