Immunohistochemical Study of Estrogen Receptor Expression in Adenoid Cystic Carcinoma and Mucoepidermoid Carcinoma of the Salivary Gland

Background: Estrogen as a steroid hormone plays a role in the differentiation and growth of various tissues, such as the breast, endometrium, colon, and prostate, as well as their cancers. The literature offers different and partly contradictory findings concerning the investigations of estrogen receptor (ER) expression in salivary gland tumors. Objectives: The aim of this study was to investigate the expression of ER in two main types of malignant salivary gland tumors, namely adenoid cystic carcinoma (ACC) and mucoepidermoid carcinoma (MEC), in an Iranian population using immunohistochemical techniques. Patients and Methods: After reviewing the patients’ records in the departments of pathology in some hospitals in the city of Yazd covering all native and southern-region patients, out of all malignant salivary glands tumors, 40 specimens were retrieved. These included 24 ACCs and 16 MECs. Following the preparation of 4 µm sections and the deparaffinization and dehydration steps, the immunohistochemical process was conducted using the antibody against estrogen receptor α (Clone1D5, DAKO, Denmark). The prepared slides were then observed under a light microscope, and the stained nuclei were counted. The data were analyzed using SPSS 17 and the generalized Fisher exact test. Results: For ACC, only one specimen expressed the ER, and this was assessed as moderate. No specimens of MEC expressed the ER. The comparison of ER expression between the two groups was not meaningful (P = 0.99). Conclusions: Regarding the findings of this study, it can be concluded that ERα possibly cannot play an important role in the tumorigenesis and prognosis of the investigated malignant salivary gland tumors.