Cancer of the gastro-intestinal tract accounts for 54 per cent of the total mortality from neoplastic disease in males (1)-an incidence which warrants particularly intensive study of the disorder. The associated metabolic abnormalities are especially important, not only because through them some clue as to etiology may be found, but also to provide information by which the mortality from difficult operative or radiological procedures may be reduced.The results of numerous clinical and experimental studies suggest that dietary factors are important in the maintenance of a normal gastrointestinal mucous membrane (2, 3). Hence, close attention has been given, in the Memorial Hospital, to the study of the nutritional status of patients with intestinal neoplasms. The results of the measurement of levels of vitamin A in the plasma, herein reported, are considered to be of special interest.
MATERIALNormal individuals were studied to establish the normal levels of vitamin A, carotene and thiamin in the blood, as well as of riboflavin in the urine. Adult laboratory technicians, house physicians, nurses, and normal young men, all apparently in good health and on adequate diets, were used as subjects.The clinical material upon which this report is based includes six different groups of patients. The first is composed of 51 patients with cancer of the gastro-intestinal tract, selected from 62 consecutive admissions to the gastric and rectal services of the Memorial Hospital. Eleven of the 62 cases were discarded because they were febrile or had received medication which might provide misleading findings.