Serum angiopoietin-1 as a prognostic marker in resected early stage lung cancer

PurposeWe evaluated the clinical significance of angiopoietins and vascular endothelial growth factor (VEGF) in patients with resected early stage lung cancer.Patients and methodsThe study enrolled 101 patients with completely resected non-small cell lung cancer (NSCLC) of stage I or II, along with 70 healthy volunteers. Serum concentrations of angiopoietin-1, angiopoietin-2, and VEGF were measured with an ELISA. Immunohistochemical expression of angiopoietin-1 was compared with the microvessel density on the lung cancer tissues.ResultsThe patients had lower serum angiopoietin-1 (32.1 ± 9.9 ng/mL vs. 39.0 ± 10.8 ng/mL, p < 0.001), higher angiopoietin-2 (1949.2 ± 1099.4 pg/mL vs. 1498.6 ± 650.0 pg/mL, p < 0.01), and higher VEGF (565.1 ± 406.3 pg/mL vs. 404.6 ± 254.8 pg/mL, p < 0.01) levels than the controls. The angiopoietin-2 level was higher in stage II than in stage I patients (p < 0.05). The levels of angiopoietin-1 (r = 0.28) and angiopoietin-2 (r = 0.36) each correlated with the VEGF level. Patients with a higher level of angiopoietin-1 (≥31.2 ng/mL) had better disease-specific and relapse-free survival than those with a lower angiopoietin-1 level (<31.2 ng/mL). Angiopoietin-1 expression negatively correlated with the microvessel density.ConclusionSerum angiopoietin-1 is a potential marker for predicting postoperative survival and recurrence in patients with early stage NSCLC.