Clinical study on the correlation between lymph node metastasis and lymphangiogenesis in colon cancer

Objective: To investigate correlation between expression of vascular endothelial growth factor-C (VEGF-C), vascular endothelial growth factor-D (VEGF-D), and expression of lymphatic microvessel density (LMVD) in colon cancer tissues. Methods: A total of 100 cases with colon cancer (colon cancer group) and 100 healthy people (control group) were randomly selected in Qingdao Center Hospital from June 2015 to December 2017. Paraffin sections of colon cancer lesions, adjacent tissues, and normal colon tissues were collected. Expression levels of VEGF-C, VEGF-D, and LMVD were examined by immunohistochemistry. Analysis of the relationship between expression levels (VEGF-C, VEGF-D, and LMVD) in colon cancer tissues and clinicopathological parameters (age, sex, Duke's staging, differentiation, pathogenic site, as well as positivity and negativity of lymph node metastasis) was performed to explore the correlation between lymph node metastasis and lymphangiogenesis. Results: Positive rates of VEGF-C and VEGF-D in the colon cancer group were significantly higher than those in the control group. The positive rate of LMVD in colon cancer adjacent tissues was significantly higher than that in healthy colon tissue (all P<0.05). In the adjacent tissues, the expression of VEGF-C and VEGF-D was significantly higher than that in adjacent metastatic lymph nodes (both P<0.05). The LMVD level in adjacent tissues with positive VEGF-C was higher than that with negative VEGF-C, and the LMVD level in adjacent tissues with positive VEGF-D was higher than that with negative VEGF-D. Differences between expression of VEGF-C, VEGF-D, and differentiation of colon cancer and lymph node metastasis were statistically significant (all P<0.05). Expression of LMVD was related to Duke's staging, differentiation, and lymph node metastasis. Conclusion: Overexpression of VEGF-C and VEGF-D can promote lymphangiogenesis, increase expression of LMVD, and lead to lymph node metastasis of colon cancer.