The interrelationship of nitrogen and phosphorus in patients with certain neoplastic diseases

ETABOLIC STUDIES OF PATIENTS with malig-M nant neoplasms in this clinic have revealed retention of nitrogen, phosphorus, and potassium during progressive neoplastic growth.This has occurred when the subjects have ingested diets that would be adequate merely to maintain body weight and nitrogen equilibrium in healthy adults of the same age and body habitus.I t is well known that malnourished patients will retain nitrogen, phosphorus, and potassium avidly when an adequate dietary intake is established.In the cancerous subjects, however, the retention of phosphorus and potassium was greater in relation to nitrogen than that seen in protein-depleted individuals with chronic non-neoplastic diseases.This phenomenon was first observed in patients with leukemia more than half a century ago.10.11, 21T h e excessive storage of phosphorus and potassium in patients with progressively growing cancers suggests that the composition of tumor tissue with respect to nitrogen, phosphorus, and potassium must be quantitatively different from that of the bulk of the noncancerous structures.Such a difference has been found from analyses of neoplastic tissues and muscle obtained by biopsy from patients with malignant neoplasms.These observations, together with metabolic-balance data, have enabled us to determine in a semiquantitative fashion the distribution of the nitrogen retained and the source of the nitrogen lost in the host and neoplastic tissues during metabolic studies carried out on many patients.Three of these patients are discussed in detail