目的

分析中下段直肠癌血管内皮生长因子（VEGF）表达状况与临床病理特征的关系，初步探讨中下段直肠癌淋巴结微转移的分子机制。

方法

应用CK-20 免疫组化技术对56例中下段直肠癌患者共计661 枚淋巴结检测微转移，同时检测肿瘤组织中VEGF 表达情况。

结果

57.1%（32/56） 中下段直肠癌VEGF 表达阳性；T3 直肠癌VEGF 表达阳性率为74.1%，明显高于T2 和T1 直肠癌的43.5%和33.3%（P=0.043）； 淋巴结转移阳性的中下段直肠癌VEGF 表达阳性率为72.4%，明显高于淋巴结转移阴性的40.7%（P=0.017）；20 例（35.7%）中下段直肠癌患者67枚（10.1%）淋巴结检出微转移，该20 例检测出淋巴结微转移的癌组织中15 例（75%）VEGF 表达阳性，而36 例未检测出淋巴结微转移的癌组织中仅有17 例 （47.2%）VEGF 表达阳性，（P=0.044）。

结论

中下段直肠癌VEGF 表达状况与浸润深度和淋巴结转移密切相关，VEGF 可能参与中下段直肠癌淋巴结微转移的发生。

Objective

To examine the expression of VEGF of middle and lower rectal carcinoma and to evaluate its correlation with lymph node micrometastases.

Methods

661 lymph nodes from 56 patients with middle and lower rectal carcinoma who received total mesorectal excision with lymphadenetomy were detected by cytokeratin-20 IHC in addition to hematoxylin and eosin （HE）staining.The expressions of VEGF of resected primary tumors were examined by IHC.

Results

The VEGF expression was positive in 32 （57.1%） specimens.74.1% T3 tumors were examined positive VEGF expression，while only 33.3% T1 tumors and 43.5% T2 tumors were examined positive VEGF expression，P=0.043.72.4% （21/29） rectal carcinomas with positive lymph nodes were examined positive VEGF expression，while only 40.7% rectal carcinomas with negative lymph nodes were examined positive VEGF expression，P=0.017.Micrometastases were identified in 67 （10.1%） lymph nodes from 20 （35.7%） patients.The expression of VEGF was positive in 15 （75%） of the 20 patients with lymph node micrometastases，and in 17 （47.2%） of the 36 patients without lymph node micrometastases.The difference between these two groups was statistically significant （P=0.044）.

Conclusion

The expression of VEGF in middle and lower rectal cancer specimens is significantly associated with depth of tumor invasion and lymph node metastasis.VEGF may play an important role in the development of lymph node micrometastases in patients with middle and lower rectal carcinoma.