Association of estrogen receptor, progesterone receptor and HER2 following neoadjuvant systemic treatment in breast cancer patients undergoing surgery.

AIMS: The aim of this study was to analyze the association between the status of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor-2 (HER2) in breast cancer with neoadjuvant therapy by using tissue biopsy and surgical specimens.
METHODS: This study included 78 patients with breast cancer, who presented to our hospital between June 1999 and June 2011, and were treated with neoadjuvant therapy and subsequent mastectomy or partial mastectomy. All clinicopathological data regarding pre-neoadjuvant biopsy and definitive surgical specimens were reviewed for accuracy. The status of ER, PR, and HER2 was determined by immunohistochemistry.
RESULTS: Paired samples from 78 women (mean age 51.4 ± 11.7 years) were successfully analyzed. A switch in the status of ER was identified in 16 patients (20 %); PR, in 18 (23 %); and HER2, in 27 (35 %). There were no significant differences in the status of ER, PR, and HER2 between the primary tumor and the resected tumor after neoadjuvant therapy. Neoadjuvant therapy does not significantly influence the status of the steroid hormone receptors and the HER2 level in our study.
CONCLUSIONS: Initial biopsy may be reliable for determining the appropriate adjuvant therapy, but final pathology are still needed to evaluate the prognosis and provided the alternative treatment when tumor recurrence. Further prospective study is needed to optimize the care available for breast cancer patients.