Vascular endothelial growth factor and psychosocial factors in colorectal cancer

BACKGROUND: Vascular endothelial growth factor (VEGF) and psychosocial factors have both been shown to have independent prognostic value in colorectal cancer. Recently, an association between VEGF and psychosocial factors has been reported in patients with ovarian cancer. METHODS: A consecutive series of eligible patients undergoing elective resection for colorectal cancer were invited to participate. Standardized measures of various aspects of quality of life (QoL) were administered 5-12 days before surgery, and again 6-8 weeks after the operation, blood samples were obtained at the same times. Solid phase ELISA was used for VEGF-A analysis using serum samples. Correlations and multiple regression analysis were used to examine the relationship between VEGF and psychosocial factors. RESULTS: One hundred and four patients with colorectal cancer were recruited. Seventy (67%) were male and the mean age was 67.6 years.A significant positive correlation was found between preoperative VEGF level and preoperative depression (r=0.227, p=0.03). Preoperative VEGF was negatively correlated with preoperative cancer-related concerns (r=-0.273, p=0.009) and positive affectivity (r=-0.219, p=0.05). Linear regression using TNM stage as a covariate showed that cancer-related concerns were an independent predictor of preoperative VEGF levels (p=0.02).Preoperative cancer-related concerns and global QoL were negatively correlated with postoperative VEGF (r=-0.381, p=0.001, r=-0.264, p=0.005), whereas preoperative depression correlated positively with postoperative VEGF (r=0.333, p=0.003). Linear regression analysis showed that preoperative HADS depression (p=0.005) and cancer-related concerns (p=0.002) were independent predictors of postoperative VEGF levels. Postoperative VEGF was significantly correlated with postoperative anxiety (r=0.249, p=0.02), depression (r=0.289, p=0.01), and functional well-being (r=-0.242, p=0.03). Linear regression analysis showed that postoperative anxiety (p=0.048), depression (p=0.013) and functional well-being (p=0.046) independently predicted postoperative VEGF-A levels. CONCLUSION: Various psychosocial factors, particularly cancer-related concerns and depression, appear to be related to preoperative and postoperative VEGF level in patients with newly diagnosed colorectal cancer. However, the clinical significance of these findings needs to be addressed in longitudinal follow-up studies of recurrence and survival. Future prognostic studies involving VEGF and related cytokines should assess psychosocial variables at various time points and include these in a multivariate analysis of outcomes.