Causes and characteristics of tumor cachexia - perspectives of dietary treatment

Tumor cachexia is a heterogeneous and dynamic phenomenon. It results from r educed food intake due to anorexia and from changes in substrate metabolism . The metabolism of cachectic tumor patients is characterized by a combinat ion of exogenous and endogenous starvation. The altered metabolism is expla ined by the immune response of the affected organism. Formation and secreti on of cytokines affect the intermediary metabolism in many ways which are s imilar to those as found in patients with tumor cachexia. Altered substrate balances distinguish tumor cachexia from the metabolic adaption in simple starvation. The changed metabolic milieu in the presence of an intact regul ation explains the limited influencability of metabolism and nutritional st atus in many patients with tumor cachexia. Tn patients with tumor cachexia, there is a pronounced metabolic preference for endogenous and exogenous fa t. Dietary strategies must aim at meeting the nutritional requirements, provid ing an increased proportion of dietary fat corresponding to the changes in metabolism and influencing the metabolic milieu. While the nutritional requ irements in various tumor diseases are well known, approaches towards influ encing the metabolism are still experimental in nature. Dietary recommendat ions for healthy individuals are intended to protect against tumor diseases but are not suitable for the treatment of tumor cachexia.