A meta-analysis of oestrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 discordance between primary breast cancer and metastases

Background The discordance in oestrogen receptor (ER), progesterone receptor (PgR) and human epidermal growth factor receptor 2 (HER2) status between primary and recurrent breast cancer is being intensively investigated and a large amount of data have been produced. However, results from different studies are heterogeneous and often conflicting. To highlight this issue, a meta-analysis of published data was performed. Methods A literature search...