[Immunocytochemical assay of estrogen receptors in puncture products of breast carcinomas].

In a pilot study, estrogen receptors (ER) were assayed on 42 surgically removed breast tumors by the following 3 methods: biochemical assay with dextran coated charcoal (DCC), Abbott immunoenzymatic (ER-EIA) and immunocytochemical (ER-ICA) technics. DCC and ER-EIA were performed on biopsy specimens while ER-ICA was run on cytocentrifugated cells obtained by fine needle aspiration (FNA). ER contents were expressed according to an index taking into account the proportion of colored neoplastic cells and the intensity of staining. Statistical correlation coefficient (Spearman and Kendall) concordance, sensitivity and specificity between the results were calculated (ER - ICA/ER - EIA: P less than 0.001, r = 0.38, concordance = 83%, sensitivity = 86%, specificity = 77%; ER - ICA/DCC: P less than 0.05, r = 0.22, concordance = 77%, sensitivity = 85%, specificity = 63%; ER - EIA/DCC: P less than 0.001, (r = 0.60). As previously reported, both immunoassays showed good agreement. The weaker but nevertheless significant correlation found with reference DCC may be due to the heterogeneity of tumoral ER content. This hypothesis is supported by the variability of ER - ICA assays on multiple FNA performed in 16 cases from our series. Use of multidirectional FNA slightly improved the results. Nevertheless, ER - ICA appear to be a good semi-quantitative method and might be helpful in the follow-up of metastasis treated with anti-estrogen, especially in small lesions not assayable by DCC.