Explain the Metabolic Alterations during Cancer?
As we have studied earlier, patients with advanced cancer experience profound anorexia, early satiety, changes in the structure/function of organs/glands/body parts, several nutritional deficiencies and weight loss. Although the cause for these symptoms is not clear but they have definitely been found to be associated with the metabolic status of the patient. There are alterations in the energy expenditure, carbohydrate, protein and fat metabolism, acid -base balance, enzyme activities, and endocrine functions. Generally, there is an increased metabolic rate. For example, it may be 10 percent greater than the normal level. But, there are variations among patients with gastrointestinal cancers. Some patients may be hyper metabolic, whereas patients with colon and rectal cancer do not show any difference. Therefore, it is evident that there can be variations among patients. Let us now discuss these metabolic changes in detail.
Cancer patients have been shown to have glucose intolerance. This is due to an increased insulin resistance and also reduced insulin secretion. There are also many reports to show that there is an increased rate of endogenous glucose production ill cancer patients. This increased production combined with other carbohydrate changes is associated with weight loss. An increased rate of Cori cycling has been reported to occur in cancer patients.