Expression of vascular endothelial growth factor-C correlates with the lymphatic microvessel density and the nodal status in oral squamous cell cancer

BACKGROUND: The cause of preferential metastatic spreading to cervical lymph nodes in oral squamous cell cancer (SCC) is not quite clear. As the density of microvessels may influence the metastatic behaviour, we were interested in how the density of blood/lymphatic microvessels are related to primary SCC and the clinical course of the disease. METHODS: Lymphatic and blood microvessels of 28 patients with oral SCC were identified immunohistochemically by antibodies against podoplanin and CD34, respectively. Lymphatic microvessel density (LVD) and blood microvessel density (MVD), and the expression of VEGF-C were determined. These findings were compared with the long-term clinicopathological data of the patients. RESULTS: LVD and MVD were significantly higher than in control tissues. The amount of lymphatic microvessels correlated positively with the expression of VEGF-C, the tumour grade, the nodal status and with later appearing metastasis. The latter three parameters, however, did not influence the clinical course of the disease. CONCLUSIONS: VEGF-C expression in oral SCC triggers lymphatic angiogenesis, which may result in a higher risk for cervical lymph node metastasis. The angiogenetic effect of VEGF-C may also favour the onset of late lymphatic and haematogenous metastases.