Expression of estrogen receptors in epithelial ovarian carcinoma

Abstract

Background/aim Epithelial ovarian cancer accounts for ∼3% of female cancers. Steroid hormones such as estrogen and progesterone are thought to play an important role in the process of carcinogenesis of ovarian tumors. There are two subtypes of the nuclear estrogen receptor (ER-α and ER-β) encoded by separate genes. This work aimed to evaluate the expression pattern of ER-α and ER-β in epithelial ovarian carcinoma and their correlation with tumor histopathological parameters and proliferating cell nuclear antigen expression as a proliferation marker. Materials and methods A total of 50 cases of epithelial ovarian carcinoma were included in this study. All cases were female patients who underwent oophorectomies or subtotal or total hysterectomies with oophorectomies. Surgical specimens were sent to Pathology Department at Kasr El-Aini hospitals and to private laboratories. The cases were graded and staged according to WHO systems. The cases were stained by hemotoxylin and eosin for histopathological grading, and they were immunohistochemically stained for ER-α, ER-β, and proliferating cell nuclear antigen using streptavidin–biotin technique. Results In this study, 56% of cases were positively stained for ER-α. It is significantly correlated with both of the tumor histological type and proliferative state of the tumors. There was a significant inverse correlation between ER-α expression and the tumor histological grade. Approximately 62% of cases were positively stained for ER-β. There was a significant inverse correlation between ER-β positivity and both of the tumor stage and proliferative state of ovarian carcinoma cases. Conclusion The loss of ER-β, not ER-α, expression in ovarian tumors may be a feature of malignant transformation suggesting its potential role as tumor suppressor gene. Determination of ER subtypes may improve response to hormonal therapy using a selective ER modulator in selected cases of ovarian carcinoma.