[Discordance of estrogen receptor status between primary and metastatic breast cancer--possible reasons and prognostic value].

The aim of the review was systematization of the data on discordance in expression of estrogen receptors between primary and metastatic breast cancer, different metastases and repeated analyses of the same tissue. The possible reasons for the phenomenon are discussed. The authors emphasize the need to analyze estrogen receptors in breast cancer metastases, regardless of the receptor status of the primary tumor, for predicting the course of the metastatic disease and providing an adequate treatment of the metastatic tumor in strict accordance with its receptor status during drug therapy. The works cited in the search engine Pub Med to May 2013 were analyzed.