Immunohistochemical Study of Vascular Endothelial Growth Factor (VEGF) and Matrilysin (MMP-7) in T1 Adenocarcinoma of the Colon and Rectum to Predict Lymph Node Metastases or Distant Metastases

Abstract

Predicting the lymph node metastatic or distant metastatic potential of T1 adenocarcinoma of the colon and rectum remains a major challenge. We investigated the role of the expressions of tumor matrilysin (MMP-7), VEGF-C and VEGF-A in predicting these metastatic potentials. Single T1 adenocarcinomas were examined and pathological tumor factors were reviewed. Immunohistochemical staining of VEGF and MMP-7 was performed and the metastatic potential was defined on the basis of the presence of lymph nodes in the specimen or the identification of other distant metastasis during follow-up examinations. There was little correlation between the IHC staining results of VEGF-A, VEGF-C and MMP-7 in the same specimen (kappa<0.1). After a 61-month median follow-up (2-131 months), 17 (11.8%) tumors showed metastatic potential, including 14 lymph node metastases and 3 distant metastases. The tumors showing high levels of MMP-7 expression had higher metastatic potentials than those with low expression (19.1% vs. 8.2%, respectively; p=0.057). Overexpression of MMP-7 generally indicated an inferior overall survival (p=0.09). In analysis of the traditional pathological tumor factors, only lymphovascular invasion showed significance in predicting metastatic potential (p=0.04). Overexpression of MMP-7 generally indicated a higher metastatic potential and inferior overall survival. Lymphovascular invasion was a significant risk factor for lymph node metastasis.