Increased Level of Annexin A1 in Bronchoalveolar Lavage Fluid as a Potential Diagnostic Indicator for Lung Cancer

Abstract

Background Annexin A1 has been implicated in various tumor types, but few studies have investigated its involvement in lung cancer. The purpose of this investigation was to quantify the annexin A1 level in bronchoalveolar lavage fluid (BALF) and analyze its usefulness in lung cancer diagnosis. Methods Annexin A1 expression was measured by immunohistochemistry and enzyme immunoassay. The sensitivity and specificity of annexin A1 for distinguishing lung cancer were determined by receiver operator characteristic (ROC) curves. Results Tumor tissues, BALF and serum of patients with lung cancer contained higher levels of annexin A1 than those of the control group of patients with benign lung diseases. Moreover, an increased level of BALF annexin A1 was closely correlated with lymphatic invasion and malignant progression of lung cancer. The sensitivity and specificity of BALF annexin A1 for distinguishing lung cancer were 94.2% and 90.2%, respectively. Conclusions Increased annexin A1 in BALF was correlated with lymphatic invasion and malignant progression of lung cancer, suggesting that it could be an indicator for discerning lung cancer and predicting outcome.