MMP9 and metastatic malignant neoplasm in the lymph nodes: Several studies in the literature have shown increased expression of MMP-9 in CRC with significance with regard to clinicopathological variables such as stages III and IV (TNM/Dukes C and D) [38–41], lymph node metastasis [40, 42], remote metastasis [37–40], peritumoral inflammatory infiltrate [43], and degree of cell differentiation II and III [38, 40, 41, 44, 45].