The pathophysiology of undernutrition in the child with cancer.

The physiologic consequences of malnutrition in children with cancer are reviewed. It is stressed that the child with cancer has a nutritional state that is no different from the average population from which the child comes. What little malnutrition is seen is calorie malnutrition. The physiologic consequences are those seen in any malnourished patient. Once the patient is being treated for cancer and the cancer course has progressed, the complications of chemotherapy and radiotherapy add to the difficulty in interpretation. However, the problem of decreased resistance to infection is one of the major problems that result from this malnutrition. The one nutrient found deficient in children with cancer is iron. Because transferrin is sensitive to prolonged protein malnutrition and because of the high level of ferritin in children with certain cancers, interpretation of laboratory values defining iron deficiency is difficult and iron homeostasis may well be very deranged.