Comparison of estrogen receptors, progesterone receptors and HER-2/neu expression between primary and metastatic breast carcinoma.

Objective: To determine whether receptor status and HER-2/neu status remains same in primary and metastatic breast carcinoma to corresponding lymph nodes of individual patients.
Methods: Estrogen receptors, progesterone receptors and HER-2/neu immunohistochemical stains were performed on primary and metastatic breast carcinoma to axillary lymph nodes in 100 patients. Data was collected on a Performa and age, tumour size, type, grade and expression of ER, PR and HER-2/neu on primary and metastatic tumours were recorded.
Results: Hormone receptor status was compared between primary and metastatic tumours. Estrogen receptor positivity was observed in 28% primary tumours which were reduced to 25% in metastatic carcinoma. Progesterone receptors were positive in 28% primary tumours as compared to 22% in metastatic tumours. Her-2/neu protein over expression was noted in 44% primary and 45% metastatic breast tumours respectively. In case to case comparison ER, PR and HER-2/neu showed 91%, 88% and 95% concordance in primary and metastatic tumours respectively.
Conclusion: ER, PR and HER-2/neu biomarkers showed significant concordance between primary and metastatic breast carcinoma.