Abstract: Objective To detect the expressions of mammalian target of rapamycin（mTOR） and vascular endothelial growth factor（VEGF） in rectal cancer，and analyze the correlation of them with invasion，metastasis and prognosis of rectal cancer. Methods Immunohistochemistry was used to detect the expressions of mTOR and VEGF in 60 cases of rectal cancer，30 cases of rectal adenoma and 10 cases of normal rectal tissues. The correlation of mTOR and VEGF with clinicopathologic features, prognosis and the relationship between them were analyzed.
Results The positive expression rate of mTOR in rectal cancer was 60.0％（36／60），higher than 36.7％（11／30）in rectal adenoma and 10.0％（1／10）in normal rectal tissues with significant difference（P＜0.05）. It was significantly correlated with preoperative CEA level，tumor differentiation，TNM stage，lymph node metastasis and distant metastasis（P＜0.05），but not with gender，age，tumor location and tumor morphology（P＞0.05）. The positive expression rate of VEGF in rectal cancer was 700％（42／60），higher than 46.7％（14／30）in rectal adenoma and 20.0％（2／10）in normal rectal tissues with significant difference（P＜0.05）.It was significantly correlated with TNM stage，lymph node metastasis and distant metastasis（P＜0.05），but not with gender，age，tumor location，tumor morphology，preoperative CEA level and tumor differentiation（P＞0.05）. The expression of mTOR and VEGF in rectal cancer tissues were positively correlated（r=0.393，P=0.002）. The median overall survival of rectal cancer patients was 39.2 months, and the 1-, 2-, 3-year survival rates were 89.4%,76.6% and 55.3%. Kaplan-Meier method showed that preoperative CEA level，TNM stage，lymph node metastasis，distant metastasis were correlated with rectal cancer prognosis（P＜0.05），while age，gender，tumor position，differentiation, tumor morphology and the expressions of mTOR and VEGF were not correlated with prognosis. Conclusion mTOR and VEGF have high expression rates in rectal cancer and positively correlated，and they may play an important role in the invasion and metastasis of rectal cancer.