Serum Angiopoietin-2 as a Clinical Marker for Lung Cancer in Patients with Solitary Pulmonary Nodules.

To evaluate the clinical significance of angiopoietin-2 (Ang-2) and vascular endothelial growth factor (VEGF) in lung cancer patients with solitary pulmonary nodule (SPN). The study enrolled 128 patients with malignant SPN, 60 patients with benign SPN, along with 40 healthy volunteers. Serum concentrations of Ang-2 and VEGF were measured by ELISA. Serum Ang-2 and VEGF levels in patients with malignant SPN were significantly higher than those in patients with benign SPN (p<0.01), and those in healthy volunteers (p<0.05). With a cutoff of 1504.8 pg/mL, the sensitivity and specificity of Ang-2 in differentiating between patients with malignant SPN and patients with benign SPN, and between patients with malignant SPN and healthy volunteers was 69.5 and 92.5%, and 80.5 and 97.5%, respectively. Additionally, higher levels of Ang-2 were associated with higher tumor stage (p<0.05). The levels of Ang-2 correlated with the VEGF level (p<0.01). In conclusion, measurement of serum Ang-2 might be a useful diagnostic marker for SPN patients.