Significance of inflammatory cytokines in the progression of colorectal cancer.

Background/aims: Circulating levels of inflammatory cytokines are associated with the disease status of cancer patients. Our purpose was to determine whether the profile of serum levels of interleukin-1 -2, -6, and -8, and tumor necrosis factor in patients with colorectal cancer correlated with tumor stages and survival.

Methodology: Serum concentrations of individual cytokines in 164 colorectal cancer patients were determined before operation by enzyme-linked immunosorbent assay. The clinical significance of each serum cytokine was evaluated in relation to tumor progression and survival.

Results: Levels of interleukin-6 and interleukin-8 were significantly higher in patients than in controls. The serum concentrations of interleukin-2 and interleukin-6 were correlated with Dukes' stages. Only the levels of interleukin-6 were found to be associated with patient survival by univariate analysis. However, multivariate analysis did not identify interleukin-6 level as an independent factor of prognosis.

Conclusions: Elevation of serum cytokines, such as interleukin-6, may be related to the development and progression of colorectal cancer. Interleukin-6 level is associated with the clinical outcome, but is not an effective prognostic predictor.