A COMPARATIVE-STUDY OF RADIOLIGAND (DCC) AND MODIFIED IMMUNOPEROXIDASE ANTIESTROGEN RECEPTOR TECHNIQUES IN BREAST-CARCINOMA

This study deals with the pattern of estrogen receptors in 52 cases of invasive breast carcinoma by comparing the ligand-binding assays with dextran-coated charcoal (DCC) to an immunoperoxidase assay (IPE) tech nique in paraffin-embedded material from the same tumor. A modificatio n of the IPE by adding cobalt chloride in the final reaction and count er-staining with eosin instead of hematoxylin was introduced. A signif icantly high correlation was found between the two compared methods (8 0.8% positivity by the DCC method and 80% by the IPE method). The corr elation was very significant in cases where the immunohistochemical gr ading was higher than 4 (according to our semi-quantitative evaluation scale of 0-8), and for these cases we suggest the IPE method as highl y specific and precise.