J Surg Oncol. 2010 Mar 1;101(3):222-7. doi: 10.1002/jso.21486.
Immunohistochemical expression of HER1, HER3, and HER4 in HER2-positive breast cancer patients treated with trastuzumab-containing neoadjuvant chemotherapy.
BACKGROUND AND OBJECTIVES: The aim of the present study was to examine the association between the expression of human epidermal receptor (HER) 1, HER3, and HER4 and pathologic complete response (pCR) in HER2-positive patients treated with trastuzumab-containing neo-adjuvant chemotherapy.
METHODS: Immunohistochemical analyses of HER1, HER3, and HER4 were performed using tumor specimens obtained from patients treated with trastuzumab-containing neoadjuvant chemotherapy. The staining intensity of each biomarker was evaluated, and the correlations between the immunohistochemical profiles and pCR were examined.
RESULTS: The present study included 44 patients with HER2-positive breast cancer treated with trastuzumab-containing neo-adjuvant chemotherapy. Seventeen patients achieved a pCR. The expressions of HER1, HER3, and HER4 were observed in 18.2%, 27.3%, and 18.2% of the specimens, respectively. A marginally significant negative correlation between the expression of HER1 and pCR was observed, irrespective of the expression of HER3 and HER4, whereas the expressions of HER3 and HER4 were not significantly correlated with pCR.
CONCLUSION: The expression of HER1 might be an independently negative predictor of pCR in HER2-positive breast cancer patients treated with trastuzumab-containing neoadjuvant chemotherapy.