The impact of progesterone receptor in prediction of complete pathological response to preoperative chemotherapy in primary breast cancer patients

BACKGROUND: The benefit of preoperative chemotherapy on outcome in breast cancer has been shown to be highest in patients with complete pathological response (pCR). The objective of this analysis was to determine the predictive value of progesterone receptor status on pCR rate in primary breast cancer patients receiving preoperative chemotherapy. METHODS: Preoperative chemotherapy was administered to 213 patients with primary breast cancer. We assessed the predictive impact of estrogen (ER) and progesterone receptor (PR) in biopsy tissue on response to preoperative chemotherapy. The association of steroid receptor status and pCR was tested by Fisher's exact and Chi-square test. RESULTS: pCR was achieved in 23 patients (10.8%). All patients experiencing pCR were PR negative (100%). ER and PR negativity was significantly associated with pCR, p = 0.00028 and p = 0.0003, respectively. CONCLUSIONS: We conclude from our results that ER and PR negativity represent valuable markers predicting pCR after primary chemotherapy. In PR-positive breast cancer patients, no single case of pCR was observed; therefore, we may recommend no preoperative chemotherapy in PR-positive patients.