Matrix Metalloproteinase 7 (MMP-7) Expression Predicts the Status of Lymph Node Metastasis in Early Gastric Cancer

Abstract

Purpose: Accurate prediction of lymph node (LN) status is of crucial importance for appropriate treatment planning in early gastric cancer (EGC). Matrix metalloproteinases (MMPs) have been shown to be involved in the pathogenesis of tumor progression and metastasis in gastric carcinoma. In this study, we investigated the association between MMPs expressions and LN metastasis in EGC. Methods: Thirty-four LN positive and 80 LN negative pT1 tumors were immunohistochemically analyzed for MMP-2, MMP-7, and MMP-9 expression. The relation of MMPs expressions to LN metastasis was analyzed in the univariate and multivariate model. Results: There were 73 men and 41 women with a mean age of 60 years. Among the pathologic characteristics, larger tumor size, submucosal invasion and lymphatic invasion were factors that are significantly associated with LN metastasis in pT1 tumors. Immunohistochemistry showed significantly higher MMP-7 expression (82.4% vs. 54.4%, P=0.005) in LN positive tumors, whereas MMP-9 (85.3% in LN positive vs. 67.5% in LN negative) and MMP-2 (70.6% in LN positive vs. 57.5% in LN negative) expression did not reach statistical significance. Multivariate analysis revealed that MMP-7 expression (OR 4.915, 95% CI 1.375∼17.573) is an independent predictor of LN metastasis in EGCs, along with lymphatic invasion by tumor cells (OR 10.337, 95% CI 2.785∼38.360). Conclusion: Our study shows that MMP-7 expression is significantly associated with LN metastasis in EGC. MMP-7 expression can be used to predict LN status in EGCs in addition to other pathological parameters.