Clinical significance of cytokines levels in exhaled breath condensate (EBC) and serum of lung cancer patients.

Abstract

e22202 Background: Cytokines are known to play an important role in carcinogenesis.The aim of this study is to measure pre-treatment concentrations of cytokines IL6, IL10, IL1β and IL8, in EBC and serum of lung cancer patients and to assess any possible association with clinicopathological variables and survival. Methods: From February 2010 to May 2011 we enrolled 73 patients with previously untreated lung cancer, 67 males and 6 females, age 67.7±9.5 years, 46 smokers and 27 ex-smokers, and 30 healthy individuals as controls. Sixty-one patients had NSCLC and 12 SCLC (5 stage I, 3 stage II, 19 stage III and 46 stage IV). EBC was collected using the Ecoscreen device (Viasys, Germany). Serum and EBC levels of cytokines were analyzed by commercially available enzyme-immunosorbent assay kits (ELISA). Results: All cytokines but IL8 were detectable in both materials. IL8 was not detected in EBC. All cytokines were significantly increased in patients with lung cancer in comparison to controls (IL6: serum P<0.0001, EBC P=0.001; IL10: serum P= 0.006, EBC P=0.037; IL1β: serum P= 0.032, EBC P=0.005; IL8 serum P=0.001). Moreover, a statistically significant correlation was found between IL10 levels in EBC and serum (P=0.001, Rho=0.334). In EBC, higher levels of IL6 were found in patients with T3-T4 disease than in those with T1-T2 [4.27 pg/ml (2.46-5.99) vs 3.12 pg/ml (1.35-5.03), P=0.036]. Furthermore, smokers had higher serum levels of IL6 compared to ex-smokers [10.19 pg/ml (4.92-17.38) vs 4.46 pg/ml (1.88-11.53), P=0.009]. Finally, lower serum levels of IL6 < median value (9.55pg/ml) were associated with improved survival (median overall survival 338 days vs 237 days Log Rank test, P= 0.046). Conclusions: Elevated levels of measured cytokines were found in both EBC and serum of lung cancer patients. Particularly, IL6 levels were related to T-stage and smoking status, while lower serum levels of IL6 with survival. These findings suggest that cytokines should be further studied in order to evaluate their diagnostic and prognostic significance. EBC could provide a simple, noninvasive and economic method for the monitoring of biomarkers in patients with lung cancer.