Expression Of Vascular Endothelial Growth Factor And E-cadherin In Head And Neck Squamous Cell Carcinoma

Background and Objective: Regional invasiveness and metastasis are important characteristics in head and neck squamous cell carcinoma. Although diagnostic and treatment techniques have improved in recent years, regional invasiveness and metastasis are still challenging treatment problems. Invasiveness and metastasis are mainly determined by properties of the primary tumor and its interaction with surrounding structures. Recent study shows that some molecular markers of primary tumor are useful for the prediction of the risk of metastasis and prognosis in patient with head and neck squamous cell carcinoma. Angiogenesis and the breakdown of the cell-cell adhesion system are correlated with the tendency of invasion and metastasis. Vascular endothelial growth factor(VEGF), one of the most important angiogenic factors contributes to perpetuating tumor growth and metastasis by enhancing angiogenesis. Reduced expression of E-cadherin is associated with tumor invasiveness and metastasis. This research investigated the expression of VEGF and E-cadherin in head and neck squamous cell carcinoma(HNSCC) and analyzed their correlation with the clinicopathologic findings and their prognostic values. Materials and Methods: Specimens of 54 head and neck squmouscell carcinoma patients who underwent primary surgical resection at our department between 1995 and 1999 were studied by immunohistochemical staining for VEGF and E-cadherin. Patients' age ranged from 31 to 78. 47 patients were male and 7 were female. According to the criteria of UICC(1997)TNM classification, patients were assigned to the following groups: 9 were classified in Tl, 19 in T2, 20 in T3, 6 in T4; and 31 patients were in NO, 18 in Nl, 5 in N2. For differentiation grade, 26 patients were in Gl, 18 in G2, 10 in G3. For VEGF evaluation, the specimens were regarded as positive when 25% or more of tumor cells were stained and negative when less than 25% of them were stained. For E-cadhering evaluation, 50% or more tumor cell staining were positive and less than 50% were negative. The relationships between VEGF or E-cadherin and the main clinicopathological characteristics and the survival rate were studied using statistical software. We examined the expression of VEGF and E-cadherin in HNSCC and their associations with T, N, and survival rate. Multivariate analysis was performed using Cox* s proportional hazard model and logistic regression analysis.Results: Posi tive expression of VEGF and E-cadherin were found in 53. 7% and 57. 4% of patients. Positive expression of VEGF was associated with advanced tumor size and lymph node metastasis and lower 5-year survival rate (P=0. 05, P=0.044, P=0. 0105). Negative expression of E-cadherin was correlated with the occurrence of lymph node metastasis, dedifferentiated grade and lower 5-year survival rate (P=0. 019, P=0.025, P=0. 0047). In the Cox proportional hazard model, VEGF and E-cadherin were powerful prognosticfactors(P=0.025, P=0.008).Conclusion: The study suggests that the expressions of VEGF and E-cadherin in HNSCC patients are correlated with lymph node metastasis. Positive VEGF and negative E-cadherin are correlated with poor prognosis. Assessment of VEGF and E-cadherin expression by immunohistochemistry is helpful on prognosis prediction for patients with head and neck squmous cell carcinoma at high risk. Such patients could potentially benefit from more aggressive therapy, such as elective neck dissection, postoperative radiotherapy and chemotherapy.FAN Hongjiang(Otolaryngology) Directed by Prof. SUN Wei...