Relationship between ER-EIA and ER-D5-Ag-IRMA in breast cancer

There is an increasing interest in the predicting of sensitivity to endocrine treatment in breast cancer, because receptor-poor tumors respond to hormonal therapy like patients without estrogen receptors. The estrogen receptor related protein (ER-D5-Ag) could be an opportunity for a new approach to identify those patients who will respond. Monoclonal antibody against estrogen receptor related protein and monoclonal antibody against estrogen receptor (1) might provide an alternative immunological approach to the problem. 53 Pre-M and 135 Post-M breast cancer specimens were analysed in predicting hormonal sensitivity in negative receptor tumors through ER-EIA and ER-D5-Ag-IRMA. Pre-M ER-EIA - ve were 70.6% ER-D5 + ve and Post-M ER-EIA - ve were 36.5% ER-D5 + ve. The Authors analysed the predictive value of ER-D5 (90.46% in Post-M; 68.28% in Pre-M) in regard to action mechanism of the two methods.