Bronchial Cytokine Changes Following Bronchial Resection and Reconstruction for Carcinoid Tumor

Abstract

As bronchial carcinoids are known to be notably rare, adequate histochemical investigations couldn’t have been carried out on these types of tumors hitherto. In this study, we investigated bronchial cytokines in a carcinoid tumor localized in the left main bronchus. Bronchial resection and reconstruction was performed without the lung resection. Bronchial lavage samples were obtained from both sides of main bronchial system preoperatively and postoperatively. TNF-α, IL-8 and IL6 levels were measured by ELÄ°SA. Preoperative TNF-α and IL-8 levels were found to be 2-folds and 5-folds higher on the tumor side respectively (TNF-α; 14.184 pg/ml and IL-8; 3359.86 pg/ml) compared to tumor-free bronchial system (TNF-α; 6.886 pg/ml, IL-8; 615.072 pg/ml). Interestingly, both cytokine levels were found to be equal and within normal ranges on both sides subsequent to bronchial resection and reconstruction. There were no significant difference in IL-6 levels between two bronchial systems preoperatively (IL-6 levels of right bronchus, 16.44 pg/ml; levels of left bronchus, 19.11 pg/ml). However, there was more than four-fold increase in postoperative levels (IL-6 level; 89.41 pg/ml). In our study, we found that preoperative TNF-α and IL-8 levels were higher compared to the postoperative ones; whereas IL-6 levels showed a significant increase, postoperatively. These findings led us through the idea that carcinoid tumors might be activating the inflammatory process among TNF-α and IL-8 and the surgical bronchoplastic procedure could be the cause of enhanced IL-6 response.