30 Gy/10f术前放疗后直肠癌组织中VEGF和VEGFR-2表达的临床病理学研究

Clinic Pathology Study on Expression of VEGF and VEGFR-2 in Rectal Cancer Treated with 30 Gy/10f Preoperative Radiotherapy

目的探讨术前放疗后直肠癌组织中VEGF和VEGFR-2表达的改变对临床预后的影响。方法收集我院自2002年8月—2007年12月接受术前放疗(30 Gy/10 f)并行开腹根治性手术的直肠癌患者116例,应用免疫组织化学的方法检测患者肿瘤组织中VEGF和VEGFR-2的表达,分析其对患者临床预后的影响。结果 VEGF的阳性表达率为74.1%(86/116),VEGFR-2的阳性表达率为42.2%(49/116),单因素和多因素分析均表明淋巴结转移(ypN分期)和VEGF表达情况是远处转移的独立风险因素;单因素分析表明VEGF和VEGFR-2的表达情况、淋巴结转移(ypN分期)、肿瘤侵犯深度(ypT分期)与患者的3年无病生存率有显著相关性(P<0.05);多因素分析表明VEGF表达情况、淋巴结转移(ypN分期)是影响直肠癌术前放疗后患者3年无病生存率的主要因素。结论 30 Gy/10 f术前放疗后VEGF的表达与临床预后有显著的相关性。

Objective To analyze the prognostic value of vascular endothelial growth factor（VEGF）and Vascular Endothelial Growth Factor Receptor-2（VEGFR-2） in patients with rectal cancer treated with 30 Gy/10 f preoperative radiotherapy and radical surgery.Methods One hundred and sixteen patients with clinical stage Ⅲ rectal cancer from Aug.2002 to Dec.2007 were studied.All patients underwent radical surgery after 30 Gy/10 f preoperative radiotherapy.Immunohistochemical examination of VEGF and VEGFR-2 were performed on the reselected tumor specimen.An immunohistochemical score established from the extension and intensity of the markers was used for analysis.The log rank test and proportional hazards regression analysis were used to calculate the probability of this biomarker associated with patients′ prognosis.Results The expressions of VEGF and VEGFR-2 were identified in 74.1%（86/116） and 42.2%（49/116） of patients.Univariate and multivariate analysis showed that lymph node metastasis（ypN stage） and positive VEGF expression were the independent risk factors for distant metastasis.Univariate analysis showed that positive expressions of VEGF and VEGFR-2,lymph node metastasis（ypN stage） and tumor invasion depth（ypT stage） were correlated with decreased 3-year disease-free survival rate（P〈0.05）.In multivariate survival analysis,positive VEGF staining and ypN＋ stage were the independent prognostic factors for disease-free survival.Subgroup analyses showed the expression of VEGF was significantly associated with the increased distant metastasis rate and decreased DFS in patients with ypN＋ stage.Conclusion VEGF expression may have potential value for predicting distant metastasis and disease-free survival in rectal cancer after 30 Gy/10 f preoperative radiotherapy.Inhibition of VEGF in combination with radiotherapy may improve the patients′ prognosis.