Significance of the Correlation Between the Expression of Interleukin 6 and Clinical Features in Patients with Non-small Cell Lung Cancer

Background: The aims of the study were to identify the significance of interleukin (IL)-6 production and to determine whether IL-6 production influences long-term survival in patients with non-small-cell lung cancer (NSCLC).

Method: A series of 90 patients with NSCLC who underwent surgery between 2005 and 2007 was analyzed. Preoperative serum IL-6 was measured, and tumor samples were immunohistochemically stained for IL-6.

Results: Serum IL-6 levels were elevated in 43 of 90 cases (47.7%), and 23 (25.5%) of 90 cases stained positively for IL-6 (P = .00265). The prognosis of patients with NSCLC who had positive immunohistochemical staining was significantly worse than that for those who had negative staining, by univariate analysis (P = .0027). Multivariate analysis indicated that tumor size, postoperative stage, and overexpression of IL-6 were independent prognostic factors.

Conclusions: The expression of IL-6 in tumor correlated with the concentration of serum IL-6, tumor progression, and overall survival in patients with NSCLC.