The stability of estrogen and progesterone receptors in patients receiving preoperative chemotherapy for locally advanced breast carcinoma.

The determination of estrogen (ER) and progesterone receptor (PR) content is routine in the management of carcinoma of the breast. Such data are commonly used to predict responses to endocrine therapy. Preoperative chemotherapy is often utilized in the treatment of patients with locally advanced carcinoma of the breast. However, little attention has been focused upon the effect of preoperative chemotherapy on hormonal receptor expression in that setting. The purpose of this study is to evaluate the effect of preoperative chemotherapy on ER and PR expression in patients with locally advanced breast carcinoma. Patients with T3 or T4 adenocarcinoma of the breast from Charity Hospital in New Orleans were studied. Levels of ER and PR were determined from tissue blocks obtained at diagnostic biopsy, as well as after the preoperative chemotherapy. The receptor levels were determined using immunohistochemistry and quantified using image analysis. We evaluated 21 locally advanced cancer patients who received at least three cycles of standard chemotherpay regimens. Of these patients, 11 achieved a partial response, with 3 achieving a complete response after preoperative chemotherapy. A total of 33 per cent of patients had a significant change in hormonal receptor content after preoperative chemotherapy. ER changed in 17%, PR in 22%, and both ER and PR in 6%. These data show that ER and/or PR expression changed in 33% of patients studied. Further, ER and PR status does not appear to predict or correlate with response to chemotherapy. This suggests that determination of ER and PR may best be performed from definitive resection specimens in patients who receive preoperative chemotherapy.