Role of Angiopoietin-2 in the control of malignant pleural effusion and survival in patients with primary lung adenocarcinoma

Aim: This study aimed to investigate the role of angiopoietin-2 (Ang-2) in the local control of malignant pleural effusion (MPE) and survival in patients with primary lung adenocarcinoma. Methods: Pleural effusion and blood samples were obtained from 85 patients with lung adenocarcinoma and MPE. Enzyme-linked immunosorbent assay was performed to investigate the expression levels of Ang-2 in pleural effusions and serums. SPSS software (Version 18.0) was used to analyze the data. Results: We found that the expression levels of Ang-2 in pleural effusion and serum were 26.82 ± 8.82 pg/mL and 358.78 ± 95.93 pg/mL, respectively. The expression level of Ang-2 in pleural effusion was found to be correlated with the control of pleural effusion. Based on receiver operating characteristic curve analysis, we found that when the cutoff value was 25.57 pg/mL, the efficacy of pleural effusion Ang-2 level in evaluating the control of pleural effusion could get the best result. Both the pleural effusion Ang-2 level and the local control of pleural effusion are independent factors affecting the prognosis of patients with lung cancer and MPE. However, this study also found that serum Ang-2 levels had no significant correlation with MPE local control or prognosis. Conclusion: Pleural effusion Ang-2 levels can be used as a molecular biomarker to predict both the MPE local control and prognosis of the MPE patients, which has significant clinical value.