Inflammatory breast carcinoma: an immunohistochemical study using monoclonal anti-pHER-2/neu, pS2, cathepsin, ER and PR.

Immunocytochemical assays were performed on frozen sections of inflammatory breast carcinomas (n = 22) using the following monoclonal antibodies (MoAb): anti-pHER2/neu, cathepsin, pS2, ER, PR and MoAb Ki67. The distribution of these proteins, known as prognostic indicators, was evaluated with an image analysis system (SAMBA, Alcatel TITN, France). On standard HE stained paraffin sections, only about 50% of inflammatory breast tumors exhibited intradermal tumor cell emboli. All tumors were strongly pHER/2neu positive. All tumors also, but to a lesser degree, were cathepsin and ki67 positive. Conversely, less than 40% were faintly ER, PR and pS2 immunoreactive. The results correlated with the high degree of malignancy of inflammatory breast carcinomas. Therefore the immuno-detection of these markers in addition to standard histological techniques appears to be a useful tool to evaluate the degree of malignancy of breast carcinomas.