Prognostic and predictive value of vascular endothelial growth factor and its soluble receptors, VEGFR-1 and VEGFR-2 levels in the sera of small cell lung cancer patients

Abstract

Small cell lung cancer (SCLC) has a rapid growth rate and is characterized by early metastases. Tumor growth is dependent on angiogenesis. Vascular endothelial growth factor (VEGF) is an important regulator of angiogenesis. Whether surveillance of pre- and post-treatment serum VEGF and especially its receptors VEGF-1 and VEGF-2 levels in SCLC patients have impact on clinical outcome is unknown. From February 2001 to January 2003, 39 consecutive patients with histological proven SCLC were enrolled into the study. Pre-treatment (n: 39) and post-treatment (n: 25) samples of the same patients were collected at the time of their response evaluation. The levels of VEGF and its receptors VEGFR-1 and VEGFR-2 were measured in the serum by quantitative sandwich enzyme immunoassay technique. The median pre-treatment serum VEGF, VEGFR-1, and VEGFR-2 levels which were significantly higher than the normal controls were 1,200 pg/ml (range, 1,414.3 +/- 956.2 pg/ml), 85 pg/ml (range, 97.8 +/- 70.7 pg/ml), and 11,550 pg/ml (range, 14,481 +/- 6,267 pg/ml), respectively. We detected a poor but positive correlation between VEGF and VEGFR-2 (r: 0.46, p: 0.003). Pre-treatment low serum VEGF (<728.5 pg/ml) value (p: 0.02) and good response to treatment (p: 0.008) were found as good prognostic factors by multivariate analysis. Low serum VEGF concentration is a significant and independent prognostic factor in SCLC patients. Surveillance of VEGF and its receptors to predict chemotherapy response is not useful. Whether the levels of serum VEGF and its receptors VEGFR-1 and VEGFR-2 have value in detecting treatment modalities of SCLC need further studies.