Cytokines in pancreatic carcinoma: correlation with phenotypic characteristics and prognosis

Abstract

Background: Cytokines have been implicated in diverse processes that are relevant to pancreatic carcinoma, including cachexia, asthenia, and tumor growth. The objective of this study was to examine the association between serum levels of proinflammatory and antiinflammatory or angiogenic cytokines and the outcomes of patients with pancreatic carcinoma.

Methods: Serum cytokine levels were measured by enzyme-linked immunosorbent assay from 51 patients with pancreatic carcinoma and from 48-62 healthy volunteers. Cytokine levels were compared with disease manifestations and overall survival.

Results: Circulating levels of vascular endothelial growth factor, tumor necrosis factor alpha, interleukin-1alpha (IL-1alpha), and IL-1beta were not elevated significantly in patients with pancreatic carcinoma, but levels of IL-6, IL-8, IL-10, and IL-1 receptor antagonist (IL-1RA) were elevated significantly (P <0.05). Cytokine levels were dichotomized based on an analysis of null Martingale residuals. Patients who had IL-6 levels > 5.2 pg/mL or IL-10 levels >9.8 pg/mL had significantly worse survival compared with patients who had lower IL-6 or IL-10 levels (P <0.05). IL-8 levels were not associated with survival differences. Patients who had IL-1RA levels <159 pg/mL had significantly worse survival compared with patients who had higher IL-1RA levels (P <0.05). Higher IL-6, IL-10, and IL-8 levels were associated with poor performance status and/or weight loss. In multivariate analysis, only T4 tumors and high IL-6 levels were selected as independent prognostic factors for poor survival.

Conclusions: Circulating levels of several cytokines were high in patients with pancreatic carcinoma, and their association with weight loss and poor performance status suggested that they may be involved in these disease manifestations. Furthermore, serum cytokine levels, in particular IL-6, may be a useful prognostic marker.