The Study of HER-2/neu, ER/PR Expression Using Immunohistochemistry (IHC) in the Iraqi Breast Cancer

Abstract

Background: Breast cancer is the most common cancer in woman that originates from the uncontrolled growth of abnormal breast cells. According to the Iraq Cancer Registry 2009, breast cancer ranks as the first between the ten common cancers in Iraq and there is a wide tendency to increase the rate of breast cancer in earlier age group. Estimation of estrogen (ER) and progesterone (PR) receptors status as well as human epidermal growth factor receptor 2(Her-2/neu) serve as specific guidance to select the patients whose benefit from endocrine therapy and provide prognostic information. The study aimed to assess the expression of ER/PR hormone receptor and Her-2/neu in breast cancer patients and correlation with various Clinicopathological aspects as a predictive biomarker.

Method: The current study was performed from the period between Jan 2015-Feb 2015 in Department of Oncology that referred to Baghdad Teaching Hospital in the Medical City. Routine staining hematoxylin and eosin (H&E) for histopathological examination and immunohistochemistry (IHC) test for ER, PR and Her-2/neu expression was conducted in all cases.

Results: This study includes total 30 cases of breast cancer. The age of patients were between 29-65 years with 47± 9.8 (mean ±SD). Majority of tumors are invasive ductal carcinomas represented 23(76.7%).There are significant differences between different scores were observed in IHC test for Her-2/neu status and showed 8(26.7%) out of 30 cases were positive expression.The ER and PR expression status was strongly associated and demonstrated in 21(70%) of cases.The most commune subgroup was Her-2/neu+, ER/PR+ seen in 10(33.3%) out of 30 breast cancer patients.

Conclusion: HER-2/neu is positively expressed in about 26.7% of breast cancer cases.The study of ER, PR status showed higher rates of positive expression70% and was strongly associated. Using IHC examination the Her-2/neu+, ER/PR+ subgroup indicates the most common subtype 10 (33.3%) compared to other tumor subtypes in breast cancer.