Pretreatment serum levels of matrix metalloproteinase-9 and vascular endothelial growth factor in non-small-cell lung cancer

Background: Matrix metalloproteinase (MMP)-9 and vascular endothelial growth factor (VEGF) are two proteins involved in angiogenesis. In the present study we investigated the association of pretreatment MMP-9 and VEGF serum levels with clinicopathological parameters and outcome in patients with non-small-cell lung cancer (NSCLC). Patients and methods: From February 1998 to October 1999, pretreatment serum levels of MMP-9 and VEGF were analysed in 118 patients with enzyme-linked immunoassays. At diagnosis 50 patients (42%) were staged as early disease (I/II), 27 patients (23%) as locally advanced (IIIA/IIIB), and 41 patients (35%) had metastatic disease (IV). In 72 of the 118 patients tumours were resected and 46 patients received combination chemotherapy with gemcitabine and vinorelbine. Results: The median survival of all 118 patients was 602 days. The 72 patients who had undergone surgery had a median survival of 972 days and the 46 patients who were treated with chemotherapy had a median survival of 298 days (P < 0.001). Resected patients with stage I/II disease and an MMP-9 serum level <= 1293 ng/ml or a VEGF serum level <= 630 pg/ml had a significantly longer survival (median survival longer than 1218 days) than patients with higher serum levels (median survival 421 days) (P = 0.001 for MMP-9; P = 0.04 for VEGF). No significant difference in survival was observed in patients with resected stage III disease. Besides tumour stage, Karnofsky performance status and gender, the pretreatment serum level of MMP-9 was identified as an independent prognostic factor in a multivariate Cox regression analysis. Conclusions: Future studies may support our hypothesis that the pretreatment serum level of MMP-9 is a new powerful prognostic marker and can help to stratify NSCLC patients with stage I/II disease into low- and high-risk groups.