Intercellular adhesion molecule expression in ductal carcinoma of the breast: Correlation of immunohistochemical staining with cytologic smear pattern

Recent studies suggest that altered expression of intercellular adhesion mo lecules (ICAM) in ductal carcinoma of the breast is associated with a highe r incidence of metastases and decreased patient survival. In addition, the presence of significant cellular dyscohesion in cytologic smear preparation s has been found to correlate with the presence of regional and distant met astases in a subset of patients. In this study, we correlate the smear patt ern in preparations taken directly from surgically excised breast tumors wi th their immunohistochemical staining pattern, using antibodies directed ag ainst a panel of ICAM. We found excellent correlation, as all three tumors with an extremely high degree of tumor cell cohesion showed strong staining with all ICAM antibodies in the vast majority (greater than or equal to 90 %) of tumor cells in corresponding tissue sections. In contrast, five rumor s displaying a largely dyscohesive smear pattern demonstrated decreased sta ining (less than or equal to 70% of tumor cells) with at least one of the I CAM antibodies used. Tumors with intermediate degrees of cellular cohesion in smear preparations showed varied patterns of ICAM staining. These findin gs support the theory that loss of ICAM expression represents the physiolog ic basis for patterns observed in cytologic smears of ductal carcinoma of t he breast. Diagn. Cytopathol. 2000;23:73-76. (C) 2000 Wiley-Liss, Inc.