[Steroid hormone receptors in mammary carcinoma. Immunohistochemical detection and prognostic significance]

Abstract

Estrogen and progesterone receptors were immunohistochemically recorded from 426 cases of primary mammary carcinoma. Immunohistochemical detection was based on monoclonal antibodies to estrogen receptor (H222) and progesterone receptor (KD68). Immunohistochemical and biochemical tests were correlated to each other with significance (p less than 0.0001) for either receptor. Some of the histological parameters exhibited relationships with the immunohistochemical receptor status. Receptor positivity of lobular, mucoid, tubular, and papillary carcinomas was more frequent than that of ductal carcinoma, whereas that of medullary carcinoma fell below ductal cases. A straight forward correlation of statistical significance was found to exist between histological tumor grade and steroid hormone receptor status. Receptor positivity of carcinomas with sizeable stroma components proved to be more frequent than that of carcinomas with lower stroma levels. Steroid hormone receptors can be immunohistochemically identified from cytological specimens, as well, though some limiting factors are implied in the latter. Thirteen percent of fine-needle aspirates provided falsely negative steroid hormone receptor findings, as compared to histological biopsy. This problem was encountered primarily in cases of low receptor positivity and high stroma content of carcinoma, factors for which only minor amounts of cell material could be obtained from puncturing. Clinical follow-up checks and evaluation of survival data revealed the immunohistochemically determined steroid hormone receptor status to be of significant importance to prognostication (ER-ICA p less than 0.00001; PgR-ICA p = 0.004). The prognosis of patients with negative estrogen and progesterone receptors was found to be worse than that of patients with positive receptor status. These studies are likely to confirm immunohistochemical determination of steroid hormone receptors, using monoclonal antibodies, to be a reliable method of great prognostic importance.