Serum IL-33 as a Diagnostic and Prognostic Marker in Nonsmall Cell Lung Cancer

Background: Interleukin-33 (IL-33) has recently been implicated in tumor immunity. The aim of this studywas to explore the clinical role of serum IL-33 in patients with non-small-cell lung cancer (NSCLC).
Methods:Sera collected from 250 healthy volunteers (HV), 256 patients with benign lung diseases (BLD) and 262 NSCLCcases were subjected to IL-33 ELISA and relationships between serum IL-33 and clinical characteristics wereevaluated.
Results: Circulating IL-33 levels were higher in the NSCLC group in comparison with the HV andBLD groups (p<0.001). Using a cut-off level 68 pg/ml (95% specificity in the HV group), IL-33 showed a gooddiagnostic performance for NSCLC. Multivariate survival analysis indicated that serum IL-33 was an independentprognostic factor in the entire NSCLC group [hazards ratio (HR) = 0.64 for low versus high IL-33 levels, 95%confidence interval (CI) 0.50–0.82; p<0.001] and in 165 selected patients with locally advanced or metastaticdisease receiving chemoradiotherapy or chemotherapy (HR 0.70, 95% CI 0.52–0.94; p=0.013).
Conclusions:IL-33 is a promising potential diagnostic and prognostic marker in NSCLC, independent of the therapeuticintervention.