Ascites can be caused by many kinds of diseases. Patients with undetermined ascites represent a diagnostic challenge. The aims of this study were to determine the diagnostic value of vascular endothelial growth factor (VEGF) in differentiation of malignant ascites from benign ascites and to investigate the clinical value of ascitic VEGF as an independent prognostic parameter. The study included 462 consecutive patients with malignant ascites and 550 patients with benign ascites, VEGF level in ascites were determined by a sandwich enzyme-linked immunosorbent assay. The survival rate was calculated by the Kaplan-Meier method and the log-rank test. Multivariate survival analysis was performed using the Cox hazards model. In our study, we found VEGF levels in malignant ascites (676.59 ± 303.86 pg/ml) were significantly higher than those in benign ascites (218.37 ± 98.15 pg/ml) (P < 0.001). Meanwhile, we also found that VEGF levels in malignant ascites from patients with ovarian cancer were higher than those with other cancers. Areas under the receiver operating characteristic (ROC) curves of ascitic VEGF was 0.940. At a cutoff value of 319.5 pg/ml, VEGF yielded a sensitivity of 89.2 % and a specificity of 88.4 %. Patients associated with the high-level VEGF value (≥613.38 pg/ml) in malignant ascites exhibited poor mean survival rates (8.3 ± 0.52 vs 15.11 ± 0.66 months, P < 0.001). In a multivariate Cox regression model, higher ascitic VEGF was an independent prognostic factor for overall survival. Planned subgroup analysis was performed for patients with tumor node metastasis (TNM) stage I. In the univariate analysis, only ascitic VEGF was associated with overall survival. VEGF was found to have a highly accurate sensitivity and specificity, suggesting that it could be considered as a new biomarker to differentiate malignant ascites from the benign one. The high level of VEGF value in malignant ascites may be used as an independent prognostic factor in patients with all stages of cancer.
Keywords: Ascites; Differential diagnosis; Prognosis; VEGF.