Antioxidants, anorexia/cachexia, and oxidative stress in patients with advanced-stage cancer

Abstract

Cancer cachexia is increasingly becoming a critical component in the comprehensive approach to cancer patients influencing morbidity, mortality, and quality of life. Therefore, its pathophysiology and the main contributing factors have been investigated with the aim of developing effective therapies. Reported findings indicate that increased production of reactive oxygen species and reduced activity of antioxidant enzymes contribute to development of anorexia and cachexia in cancer. Oxidative stress, almost always accompanying cancer cachexia, may be counteracted by effective antioxidant treatments: in this review, the most relevant recent clinical approaches addressing this target are reported. Fairly advanced clinical data on efficacy of and antioxidants in advanced cancer patients are promising, but the best way to administer and combine them with other agents, the optimal dose, and timing remain uncertain. However, because cachexia is a multifactorial syndrome, therapeutic approaches targeting a single contributing factor may be inadequate: targeting oxidative stress only one determinant is addressed, thereby limiting clinical efficacy. Therefore, antioxidants should be included in developing a therapeutic approach for cachectic cancer patients, however, they cannot encompass all symptoms of cancer cachexia. Recent evidence seems to confirm that the treatment of cancer cachexia, a multifactorial syndrome, is more likely to yield success with a multitargeted approach.