Evaluation of ER-α, ER-β1 and ER-β2 expression and correlation with clinicopathologic factors in invasive luminal subtype breast cancers

Purpose Luminal subtype breast cancer is defined as oestrogen receptor (ER)- and/or progesterone receptor (PR)-positive breast cancer. We detected the expression of ER-α, ER-β1 and ER-β2 in the tissue samples of invasive luminal subtype breast cancer patients, evaluated the correlations between these ER statuses and prognosis, and tried to clarify whether the status of ER-α isoforms provides clinically useful information further to what is already provided by the traditional ER-α/PR assay.