Weight loss in patients with head and neck cancer: malnutrition or tumour effect?

Isotopic infusions, hormone assays and calorimetry have been used to test the hypothesis that weight loss in head and neck cancer (HNC) patients is not due to pure malnutrition, but that a large component of the weight loss in these patients is a consequence of the metabolic effects induced by the tumour on the host. Twelve patients with advanced HNC were compared with eight depleted patients (DEP) who did not have cancer. Both groups had lost more than 10% of well body weight. Neither patient group had an elevated rate of energy expenditure as determined by calorimetry. Both glucose production and plasma glucose clearance were not significantly different between the two groups. The percentage of glucose production undergoing recycling to lactate was elevated in the HNC patients compared with the DEP patients. In addition, the percentage of glucose undergoing oxidation to CO2 was significantly lower in the HNC patients compared with the corresponding DEP value. The HNC patients were significantly more catabolic than the DEP patients and their serum cortisol concentration was also significantly elevated. Although the basal plasma insulin concentrations were similar in the two groups, the response to glucose infusion was markedly less in the HNC patients. It is concluded that patients with advanced HNC are metabolically different from starving patients, although both may lose a similar amount of weight. In particular, the adaptive response of protein conservation seen in simple starvation does not occur in the HNC patient.