Investigating the utility of serum cytokine measurements in a multi-institutional cancer anorexia/weight loss trial

Background: Interleukin-1 beta (IL-1beta), tumor necrosis factor alpha (TNFalpha), and interleukin-6 (IL-6) have been implicated in the cancer anorexia/weight loss syndrome. However, previous smaller studies have yielded conflicting results as to whether circulating, serum concentrations of these cytokines are in fact elevated. As the translational component of a large multi-institutional trial, this study assessed the clinical value of serum concentrations of these cytokines in patients with this syndrome. Methods: Patients with incurable cancer with anorexia and/or weight loss were eligible. All underwent weekly weight measurements and appetite assessment for the first month and then monthly assessments thereafter. Serum was obtained at baseline and at 1 month, and all three cytokines were measured with the Immunolite assay. Results: A total of 118 patients participated. At baseline, 99%, 54%, and 47% of patients' samples had undetectable IL-1beta, TNFalpha, and IL-6, respectively. Similar results were obtained at 1 month. No correlations were observed between serum cytokine concentrations and changes in weight or appetite. Baseline serum IL-6 predicted a diminished survival but only after adjustment for age and cancer site. Conclusion: Serum concentrations of IL-1beta, TNFalpha, and IL-6, as measured in this study, provide data of limited clinical value for patients with the cancer anorexia/weight loss syndrome.