Expression of Estrogen Receptor and Progesterone Receptor in Epithelial Ovarian Tumors

Abstract Expression of Estrogen Receptor and Progesterone Receptor in Epithelial Ovarian Tumors Sujitra        Tanvanich               MSc (Pathobiology)* Siriwan       Tangjitgamol         MD*,** Sumonmal Manusirivithaya   MD, MSc (Clinical Epidemiology)** Somneuk    Jesadapatarakul MD* * Department of Anatomical Pathology, BMA Medical College and Vajira Hospital ** Department of Obstetrics and Gynecology, BMA Medical College and Vajira Hospital Objectives: To examine the expression of estrogen receptor (ER) and progesterone receptor (PR) in epithelial ovarian tumors and their associations with status of malignancy, histopathologic subtypes and grading. Study design: descriptive study. Subjects: Tissue of epithelial ovarian tumors resected at the BMA Medical College and Vajira Hospital between 1996-2005. Methods: The patients with epithelial ovarian tumors who were operated in our institution were identified. Samples of formalin-fixed, paraffin-embedded ovarian tumor tissue of patients were retrieved and processed for ER and PR immunohistochemical study. Data collected were: age, status of malignancy, tumor histologic subtype, and grade of malignant tumor. Expression of ER, PR and their associations with these pathological data were studied. Main outcome measures: Immunohistochemical expression of estrogen and progesterone receptors. Results: During the study period, 191 patients with epithelial ovarian tumors who were operated in our institution were identified. Mean age of the patients was 47.7 ± 14.6 years. Positive immunohistochemical expression of ER and PR were found in 29.8% and 34.0% respectively. ER expression was higher in malignant tumors than borderline and benign tumors, 39.6% versus 25.9% and 13.8% respectively while the expression of PR showed no different expression, 33.0% versus 33.3% and 36.2% respectively. Endometrioid tumors showed highest ER and PR expression 57.1% and 66.7% respectively, while clear cell tumors showed lowest expression of ER (5.9%) and mucinous for PR expression (9.6%). Focusing only on the malignant tumors, we found that the expression of ER and PR in mucinous and clear cell carcinomas were significantly lower than other cell types, 6.8% versus 62.9% for ER and 9.1% versus 50.0% for PR expression. Positive ER expression was significantly lower in well differentiated than moderately and poorly differentiated carcinomas, 11.8% versus 48.6% and 42.6% whereas there was no significant association between PR and grade of tumor. Conclusions: We demonstrated 29.8% of ER and 34.0% of PR expression in epithelial ovarian tumors. Expression of ER in malignant tumors was higher than benign and borderline tumors, whereas the expressions of PR of these tumors were nearly the same. Both receptors were lowly expressed in clear cell and mucinous tumors. ER expression was lower in well differentiated than moderately and poorly differentiated tumors while there was no significant association between PR and grade of tumors. Vajira Med J 2008 ; 52 : 249-256