Vascular endothelial growth factor-C (VEGF-C), VEGF-D, VEGF receptor-3 (VEGFR-3) and podoplanin (PDPN) are involved in the spread of cancer. The current study evaluated VEGF-C, VEGF-D, VEGFR-3 and PDPN mRNA expression levels in 84 esophageal cancer samples from patients who had undergone surgery according to reverse transcription-quantitative polymerase chain reaction, and correlated the results with the clinicopathological features. The effects on lymph node metastasis and survival were identified by performing univariate and multivariate analyses. VEGF-C, PDPN, VEGF-D and VEGFR-3 were overexpressed in 52.4, 52.4, 32.1 and 51.2% of esophageal cancer samples, respectively. Furthermore, the expression of VEGF-C and PDPN was significantly correlated with lymph node metastasis, depth of tumor invasion and tumor stage (P<0.05). Logistic regression analysis identified tumor size (P=0.001), depth of invasion (P=0.002) and PDPN mRNA expression (P=0.022) as significant multivariable predictors of regional lymph node metastasis. Upon univariate survival analysis, the depth of tumor invasion, lymph node metastasis, histological grade, tumor stage, tumor size, residual tumor, and VEGF-C and PDPN mRNA expression were identified to be significant independent prognostic factors for overall survival (OS) time. Additionally, multivariate analysis identified tumor size (P=0.049), residual tumor (P<0.001) and PDPN mRNA expression (P=0.02) as independent factors for poor OS time. Thus, it was concluded that PDPN mRNA expression may serve as predictor for regional lymph node metastasis, and that VEGF-C and PDPN may be prognostic factors in patients with resected esophageal cancer.
Keywords: esophageal cancer; lymph node metastasis; podoplanin mRNA; prognosis; vascular endothelial growth factor-C mRNA.