Reduced or Loss of ER and PR Receptor Expression in Metastatic Breast Cancer
Rajarsi Gupta, Carmen Tornos, Meenakshi Singh, Brian O'Hea, Jingxuan Liu. Stony Brook University Medical Center, Stony Brook, NY
Background: ER and PR expression in metastatic/recurrent breast cancer can be used to confirm the origin of the tumor and determine the use of hormonal therapy.
Design: A computer search for metastatic breast cancer cases was performed from January 1998 to September 2011. The ER and PR profile of these metastases was compared to the profile of the primary breast tumor. Sixty two metastases had available ER and PR status information in both the primary tumor and the metastases. We selected the cases that have differences of 50% or more with regard to either ER or PR expression between the primary and metastatic tumors, and the cases where the ER or PR expression in the metastatic tumors decreased to 0% from any level of expression in the primary tumors. Seven cases meet the criteria.
Results: In 55 of the 62 cases (88.7%), the ER and PR profiles have differences of less than 50% or no differences at all. In seven of the 62 cases (11.2%), the differences are significant (>50%). ER expression is reduced in 3 cases; PR expression is reduced in 4 cases (Table).
|Metastatic Foci||ER (%) of Metastasis||PR (%) of Metastasis||Time between Primary and Met||Primary ER (%)||Primary PR (%)||Difference in ER (%)||Difference in PR (%)|
|Femoral reamings||46||8||2 yrs||80||90||-34%||-82%|
|Upper eyelid and orbicularis muscle||30||0||2 yrs||90||5-30||-60%||-5-30%|
|Femoral condyle||0||0||8 yrs||90||10||-90%||-10%|