Body composition of patients with malnutrition and cancer. Summary of methods of assessment.

Body composition is determined, by multiple isotope dilution, to obtain an accurate and precise measure of the nutritional state and to evaluate the response to specialized nutritional therapy. Malnutrition results in a loss of body cell mass (BCM) accompanied by an expansion of the extracellular mass (ECM). Thus, in 75 malnourished patients the BCM was 40.5% less and the ECM was 24.6% greater than that of 25 normal volunteers, resulting in a body weight difference of only 16.3%. In 19 normally nourished patients undergoing major elective surgery, by the fifth postoperative day the BCM decreased by 13.9% and the ECM increased by 9.6%, resulting in a 3.9% loss of body weight. During an 18-month period, body composition was determined in 43 patients with cancer. Eighteen patients were nutritionally normal, whereas 25 were malnourished. In 17 of the malnourished patients, body composition was determined at 2-week intervals while they were receiving total parenteral nutrition (TPN). Body composition remained unchanged in nine but improved in eight, with a BCM increase from 14.6 +/- 1.1 to 18.4 +/- 1.2 kg. These data demonstrated that an improvement in the nutritional state can be achieved in patients with cancer.