Serum spleen tyrosine kinase and vascular endothelial growth factor-C levels predict lymph node metastasis of oesophageal squamous cell carcinoma

Lymph node involvement is a key feature and an independent prognostic factor of oesophageal squamous cell carcinoma. However, an accurate and robust assay to predict the lymphatic spread of oesophageal squamous cell carcinoma is unavailable. The purpose of this study was to determine whether serum vascular endothelial growth factor-C (VEGF-C) and spleen tyrosine kinase levels are potential markers of lymph node metastasis in patients with oesophageal squamous cell carcinoma. In the study, 108 patients with oesophageal squamous cell carcinoma and 24 healthy subjects participated. Serum spleen tyrosine kinase and VEGF-C concentrations were examined by enzyme-linked immunosorbent assays. Patients with oesophageal squamous cell carcinoma had significantly elevated VEGF-C and decreased spleen tyrosine kinase in serum when compared with normal controls (P < 0.05). Pearson's correlation analysis revealed that serum spleen tyrosine kinase was negatively correlated with the serum VEGF-C level in oesophageal squamous cell carcinoma patients (r = -0.453, P = 0.000). In addition, surgical resections of the oesophageal tumour profoundly brought both serum spleen tyrosine kinase and VEGF-C closer to the normal range at 2 weeks after operation (P < 0.05). Statistical analysis showed that enhanced serum VEGF-C and reduced spleen tyrosine kinase significantly correlated with the stage of regional lymph node metastasis, tumour size and the status of primary tumour extension, but not with other clinicopathological features of the patients (P < 0.05). Our data suggest that both serum spleen tyrosine kinase and VEGF-C levels are valuable in the preoperative evaluation of lymph node metastasis in patients with oesophageal squamous cell carcinoma.