Objective: To investigate the expression of cell adhesion molecules and Their significance in invasive micropapillary carcinoma (IMPC) of the breast.
Methods: Immunohistochemical study for E-cadherin was performed on 64 cases of IMPC and 57 cases of invasive ductal carcinoma (IDC).
Results: E-cadherin was mainly expressed on the cell membrane of tumor cells. The expression of E-cadherin in IMPC (85.9%, 55/64) was significantly higher than that in IDC (43.9%, 25/57). E-cadherin expressed in the intercellular contact surface of IMPC cells. In contrast, it was weakly positive/not expressed on the outer membranous surface of the tumor clusters in IMPC. The rate of lymph node metastasis in IMPC (85.9%, 55/64) was significantly higher than that in IDC (52.6%, 30/57), the rate of alpha-catenin and beta-catenin coexpression in IMPC (45.1%, 26/51) with lymph node metastasis and E-cadherin normal expression was also significantly higher than that in IDC (15.4%, 2/13).
Conclusion: Weak cell adhesion molecule expression on the outer surface of IMPC cell clusters, in contrast to strong cohesion in intercellular contact surface, may help to explain the high metastatic potential of this type of breast cancer.