Nutritional support of the cancer patient.

Cachexia is common in patients with advanced neoplastic disease, and beyond certain levels, is associated with decreased survival. Depletion of vitamins and minerals may co-exist with protein-calorie undernutrition. The causes of the cancer cachexia syndrome may include decreased food intake, increased fecal and urinary nutrient losses, and abnormal metabolic pathways in both the host and the tumor. The complex nature of weight loss in cancer makes restoration of lean body mass more difficult in cancer than in non-cancer undernutrition. Non-volitional feeding (hyperalimentation) frequently causes cancer patients to gain weight, but this weight may be more fat and water than lean body mass. Hyperalimentation has not yet been shown to prolong survival in cancer, but additional nutritional support studies are in progress.