The Effect of Neoadjuvant Chemotherapy on the Biological Prognostic Markers in Breast Cancer Patients

Ha, Gi Won; Youn, Hyun Jo; Jung, Sung Hoo

Abstract

PURPOSE: The selection of systemic therapy for breast cancer is based on the expression pattern of biological prognostic markers. Neoadjuvant chemotherapy has been considered the standard care for locally advanced breast cancer. However, its effect on the expression of biological prognostic markers is controversial. The aim of this study was to determine whether neoadjuvant chemotherapy may alter these expression patterns in patients suffering with breast cancer.
METHODS
We determined the protein expression levels of estrogen receptor (ER), progesterone receptor (PR), p53 and HER-2/neu in the preoperative core needle biopsies and the final surgical specimens from 15 patients who received neoadjuvant chemotherapy between January 2002 and June 2007. As a control group, we analyzed the samples from patients who did not receive neoadjuvant chemotherapy.
RESULTS
The pathologic complete tumor response rate (pCR) of the neoadjuvant chemotherapy group was 6.7% (1/15). Of those patients who did not achieve a pCR (n=14), no significant differences in the biological prognostic markers expression were observed between the two groups. Alteration of the ER or PR status occurred in 42.8% (6/14) of the patients after neoadjuvant chemotherapy and in 14.3% (2/14) of the control patients, showing there was no significant difference between the two groups (P=0.210). The hormonal receptor status was changed in 3 cases (21.4%) after neoadjuvant chemotherapy.
CONCLUSION
There were no significant differences for the changes in the expression of ER, PR, p53 and HER-2/neu from the preoperative core needle biopsy to the final surgical specimens between those patients who had received neoadjuvant chemotherapy and those patients who didn't. However, changes of the ER or PR status and the hormonal receptor status occurred in 42.8% and 21.4%, respectively, of the patients who underwent neoadjuvant chemotherapy. As these changes may impact treatment, we suggest that immunohistochemical assay is necessary before and after neoadjuvant chemotherapy in patients with breast cancer.