Nutrient intake and nitrogen metabolism in cancer patients during oncological chemotherapy.

Aggressive oncological chemotherapy often impairs the nutritional status of tumor patients. To evaluate the pathogenetic mechanisms, food intake in 13 cancer patients was investigated in correlation with nitrogen losses, N balances, muscle wasting, and weight course, during cytostatic therapy. Median daily N and energy intakes were reduced only in patients with weight loss [0.55 g protein, 16.5 kcal/kg ideal body wt (IBW)]. Patients with constant weight had the same intake as control subjects (1.27 g protein, 37.2 kcal IBW). N balances and creatinine height index (CHI) correlated with daily nutrient intake. Fecal N excretions did not correlate with urinary losses; there was no excess of fecal N loss because of cytostatic treatment. The impairment of cancer patients' nutritional status seems to depend primarily on the decrease of spontaneous oral intake as a consequence of the side effects of tumor therapy. Changes in CHI, compared before and after chemotherapy, indicated muscle wasting of weight-losing patients.