Detection of steroid receptors in breast cancer: relationship between EIA and IHC methods

The efficiency of EIA and IHC (frozen tissue) in the detection of ER and PR in 51 breast cancers were compared. ER were detected in 51% of cases by IHC and in 49% of tumours by EIA. PR were detected in 56.8% of cases by IHC and in 54.8% of tumours by EIA. Concordance of the results of IHC and EIA reached 78.4% in ER and 82.4% in PR detection. Discordance between IHC and EIA seems to be related to minor changes in sensibility of methods, but we cannot conclude that one of the two techniques is superior to the other in the detection of hormonal receptors. There is a common trend of association between low grade of histologic or nuclear malignancy and a high expression of hormonal receptors.