[Estrogen receptor status in breast carcinoma. Results of comparative immunohistochemical and biochemical studies]

Comparative biochemical and immunohistochemical investigations on receptors were performed on 100 breast cancers of different types. The biochemical analysis was carried out by means of radioimmunoassay (RIA) and immunohistochemical detection was performed with monoclonal antibodies against nuclear receptor protein (ER-ICA, Abbott Lab.). The semiquantitative evaluation is based on a histological score considering a graduated staining intensity and the percentage of positively reacting cells. The results of the two methods corresponded in 92% in positive and in 68% in negative receptor detection. The age-dependence is confirmed. The nuclear grading and histological grading show that the number of estrogen receptors gradually decreases with increasing degree of malignancy of the carcinomas. The advantage of immunohistochemical receptor assay consists in the microscopic investigation of homogeneous and heterogeneous degrees of intensity as well as in the possibility of determining receptor status in very small breast cancers, in punch biopsies and in tumours in which the tumour parenchyma is largely necrotic, sclerosed or surrounded by large amounts of mucus.