Expression Of VEGF-C,VEGFR-3 And LVD In Nasopharyngeal Carcinoma And Its Relation To Lymphatic Metastasis And Prognosis

To detect the expression of vascular endothelial growth factor-C(VEGF-C) , vascular endothelial growth factor receptor-3(VEGFR-3)and lymphatic-vessel density(LVD) in biopsy specimens of nasopharyngeal carcinoma (NPC) before radiotherapy and to investigate their associations with clinicopathologic characters , node recurrence and survival rate .It may provid a new method to understand the mechanisms of lymphatic metastasis in NPC. MethodsExpression of VEGF-C , VEGFR-3 and LVD in paraffins embedded specimens from 55 cases with NPC was studied with PV-9000 immunohistochemical staining . The correlation analysis of VEGF-C ,VEGFR-3 expression and LVD were carried out ,as well as their relations to clinicopathologic characters ,lymph node recurrence and 3-year survival rate.Results1.The positive rate of VEGF-C ,VEGFR-3 and the mean LVD in 55 cases with NPC was 76.4%(42/55),81.8%(45/55)and 17.4±6.3 respectively,and there were significant differences between node positive group and node negative group.The expression of VEGF-C and VEGFR-3 was significantly lower in stageⅠ,Ⅱgroup than stageⅢ,Ⅳgroup,whereas the expression of VEGF-C,VEGFR-3 and LVD was not related to age,sex or clinical T stage. 2. Positive correlation between the expression of VEGF-C and VEGFR-3 was observed. With the increase of the expression of VEGF-C and VEGFR-3,LVD increased and significant differences among different VEGF-C or VEGFR-3 groups were observed.Positive correlations were also observed between the expression of VEGF-C or VEGFR-3 and LVD by Spearman correlation analysis. 3.The 3-year node control rate was 80%. N stage and LVD was realated to lymph node recurrence in univariate analysis,but in multivariate analysis ,only N stage was independent prognostic factor for lymph node recurrence.4. The 3-year cumulative survival rate was 61%. There were statistically significant differences between low and high LVD group or low and high expression group of VEGF-C / VEGFR-3 by using the Log- rank test. The expression of VEGF-C , LVD and clinical stage were independent prognostic factors for survival rate in multivariate analysisConclusions1.The binding of VEGF-C and its specfic receptor,VEGFR-3 could promote lymphangiogenesis and node metastasis in NPC. 2. The 3-year survival rate in high expression group of VEGF-C ,VEGFR-3 and LVD was lower than that in low expression group in NPC .Patients who had high VEGF-C expression and high LVD may have poor prognosis.3. High LVD may indicate the risk of lymph node recurrence in patients with NPC.