Why cancer patients have anorexia.

The theory has been advanced that the anorexia of cancer is the result of anorexigenic peptides and of other intermediary metabolites produced by the cancer and the tumor-bearing host. These metabolites are the signals to peripheral receptors and to the brain centers and are responsible for the state of satiety and aversion to food. Although the only effective way to stimulate the appetite of the cancer patient is to control the cancer, efforts should be made to increase the calorie intake even in the presence of anorexia and to maintain a calorie equilibrium. However, controlled studies have not shown that forced feeding can reverse for long periods the progressive tissue wasting process or prolong the cancer patient's survival.