Predictive and prognostic value of LPS-stimulated cytokine secretion in metastatic non-small cell lung cancer

Cancer patients usually develop malnutrition which may alter their innate immune system integrity. The aim of this study was to investigate the clinical relevance of chemokine response after lipopolysaccharide (LPS)-stimulation in metastatic non-small cell lung cancer (NSCLC). Blood samples from metastatic NSCLC patients were incubated with LPS before the onset of systemic therapy. Interleukin (IL)-6 and IL-8 levels at baseline and after LPS-stimulation were measured and the fold change compared to baseline levels was evaluated as the stimulation index for each cytokine per patient. Results were correlated with sex, age, smoking status, histologic subtype, performance status (PS), albumin, Mini Nutritional Assessment (MNA) status and clinical outcomes. Totally 103 patients were evaluated. Mean (±SD) stimulation index was 37.6 (±57.8) for IL-6 and 76.7 (±133.4) for IL-8. The disease control rate after first-line chemotherapy was 44/80 (55 %) and the mean (±SD) progression-free survival (PFS) and overall survival (OS) were 4.2 (±3.9) and 9.2 (±1.1) months, respectively. MNA, PS, albumin, IL-6 and IL-8 stimulation indices were univariately associated with PFS and OS. IL-8 stimulation index emerged as an independent predictor of both PFS and OS, along with PS, and albumin levels. The extent of IL-6 and IL-8 stimulation after ex vivo induction with LPS is an important predictor of clinical outcome in metastatic NSCLC patients.