Quantitative analysis of changes in ER, PR and HER2 expression in primary breast cancer and paired nodal metastases

摘要

Background: Assessment of receptors [estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2)] is routinely carried out on primary tumour in order to select appropriate adjuvant therapy; the same analysis is not carried out on nodal metastases. Since de novo resistance to therapy is common, we quantified differences in receptor expression between primary and nodal disease in order to assess whether this might contribute to therapeutic resistance.