Weight change and peptide hormone responses in patients receiving interferon

The purpose of this pilot study was to describe body weight status and peptide hormone responses in patients receiving interferon (IFN) therapy for renal cell carcinoma. Eighteen patients were on therapy for approximately two to three months. Mean weight loss of the patients was 2.2 +/- 0.9 kg (mean +/- SEM) or 4.9 +/- 0.9% of prestudy weight. Of the 18 patients, 6 were further evaluated for peptide hormone responses to meal stimulation before and after treatment (mean: 1.5 months). These subjects had a mean weight loss of 4.3 +/- 1.6 kg or 7.0 +/- 3.5% of prestudy weight. Blood was drawn from subjects before and six times after they had consumed a defined formula liquid meal to provoke enteroinsular peptide release. It was discovered that one-half of this group (n = 3; Group A) had some glucose intolerance following IFN therapy, despite increased response of insulin, gastric inhibitory polypeptide (GIP), and pancreatic polypeptide (PP) to meal stimulation. Further, patients in Group A had a weight loss of -11.7 +/- 2.7% of prestudy weight, whereas the other three patients (Group B) experienced a mean loss of -2.3 +/- 1.2% (p less than 0.04). The three subjects characterized by the smaller loss of prestudy weight (Group B) had decreased glucose response to meal stimulation, despite decreased responses of insulin and GIP. Response of PP was slightly increased with treatment in group B, but the increase was not as large as that in Group A. These data may suggest that extreme weight loss and altered peptide hormone response occur in a subset of cancer patients receiving interferon therapy.