Discordance of Estrogen Receptor (ER), Progesterone Receptor (PR) and Her-2/Neu Expression between Primary Breast Carcinoma and Brain Metastasis.
Shveta Hooda, Gloria Carter, Mamatha Chivukula. UPMC, Pittsburgh, PA
Background: About a third of invasive breast carcinomas metastasize to brain. Breast cancer patients who developed brain metastasis had higher proportions of triple-negative and HER2+/ER- tumor expression. There is paucity of information on the discordance of Estrogen Receptor(ER), Progesterone Receptor (PR) and Her-2/neu status between primary and metastatic breast carcinoma although this might affect the systemic therapy of the patient's metastatic disease. The aim of our study is to analyze the ER, PR and Her2/neu expression of primary breast carcinoma that metastasize to brain.
Design: We performed a retrospective analysis of 20 patients with breast carcinoma with documented brain metastasis. We searched the laboratory information system (LIS) (Copath plus) for the ER, PR and Her2/neu data on these patients.
Results: Only the cases with paired data available on atleast one of the markers were included in the study. We found no discordance in ER staining between the primary and metastases. The discordance rate for PR was 22% and for HER2/neu was 7%. Out of the 2 cases that showed discordance in PR staining, 1 case lost PR and the other gained PR in metastases. We found Her2/neu discordance in only 1 case which showed positivity in the metastases.
|Concordant cases||Discordant cases|
|ER (n=11)||11 (100%)||0|
|PR (n=9)||7 (78%)||2 (22%)|
|Her2/neu (n=14)||13 (93%)||1 (7%)|