[Estrogen receptor in human breast cancer: relationship between the receptor contents and the histological and cytomorphological characteristics].

Cytoplasmic estrogen receptor (ERC), nuclear estrogen receptor (ERN), and cytoplasmic progesterone receptor (PRC) were studied in 217 human breast cancers. ERC was found in 48.4%, ERN in 37.8%, and PRC in 32.7%. Histological grade was significantly correlated with ERC, ERN and PRC. Well-differentiated tumors were more frequently positive for the receptors while poorly differentiated tumors were generally negative for the receptors. Seventy one percent of the most differentiated tumors were ERC(+) ERN(+) PRC(+) and ERC(+) ERN(+) PRC(-). The histological grading system consists of tubule formation, nuclear pleomorphism and mitotic activity. There were significant correlations of receptor contents with nuclear pleomorphism and more mitotic activity. This was also confirmed by the study on the relationships between receptor contents and thymidine labeling index or mitotic index. The possibilities of receptors decreased with an increase in nuclear diameter. And there was a significant correlation between the receptor contents and the numbers of intracellular organellas in ultrastructural features of breast cancer cells. Among 33 cases of advanced or metastatic breast cancer submitted to endocrine therapy, 13 cases showed clinical response (CR or PR) These cases were both ERC and ERN positive independently of PRC status. Therefore, it is suggested that hormone receptor may be used as an independent prognostic factor in breast cancer.