Abstract
Objective: To evaluate the immunohistochemical expression of estrogen receptor alpha (ERα) in patients with endometrial carcinoma in Mosul city and to correlate it with various clinical and pathological parameters.
Methods: Sixty cases of endometrial carcinoma were collected from Al-Batool Teaching Hospital, Al-Khansaa Teaching Hospital, private laboratories during a period extending from January 2007 – to January 2009. The tumors were typed according to the World Health Organization classification system and graded according to FIGO grading system. The expression of ERα was evaluated immunohistochemically; the findings were correlated with the age of the patients, type and grade of the tumor and the extent of myometrial invasion. ERα status was assessed immunohistochemically on formalin fixed paraffin embedded (FFPE) tissue of tumor, using monoclonal mouse antibody (IgG1) clone ID5. A semi-quantitative score was used to record the results of ERα staining according to the system established by Carcangiu et al.
Results: The patients age ranged from 31 to 70 years (mean = 56.5). Histopathological typing revealed that 55 cases (91.7%) were endometrioid carcinoma which included [46 cases (83.6%) typical, 5 cases (9.1%) villoglandular, 3 cases (5.5%) adenosquamous and 1 case (1.8%) secretory type] and 5 cases (8.3%) were non-endometrioid carcinoma [2 cases (40%) papillary serous and 3 cases (60%) with clear cell type]. The overall expression of ERα in endometrial carcinoma is 60%, ERα was failed to show a statistically significant correlation with the age (P value = 0.9). A statistically significant association was found between ERα expression and types of endometrial carcinoma (P value = 0.004). In endometrioid carcinoma, the ERα expression was detected in 65.5%, whereas non-endometrioid carcinoma failed to demonstrate positivity (0.0%). There was a significant inverse relation between ERα expression and the grade of the tumor (P value = 0.001). There was a significant inverse relation between ERα expression and the extent of myometrial invasion (P value = 0.004).
Conclusions: ER α is expressed in 60% of endometrial carcinoma in Mosul city. ERα is significantly expressed in endometrioid carcinoma, while it is negative in non-endometrioid carcinoma. ERα expression is inversely correlated with the grade of endometriod carcinoma and the extent of myometrial invasion.
Keywords: ERα , endometrial carcinoma, endometrioid carcinoma, non-endometrioid carcinoma.