Immunohistochemical expression of HER1, HER3, and HER4 in HER2-positive breast cancer patients treated with trastuzumab-containing neoadjuvant chemotherapy.
OBJECTIVE
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.


CONCLUSIONS
The expression of HER1 might be an independently negative predictor of pCR in HER2-positive breast cancer patients treated with trastuzumab-containing neoadjuvant chemotherapy.
Yonemori
Kan
K
Breast and Medical Oncology Division, National Cancer Center Hospital, Chuo-ku, Tokyo, Japan. kyonemor@ncc.go.jp
Tsuta
Koji
K
Shimizu
Chikako
C
Hatanaka
Yutaka
Y
Hirakawa
Akihiro
A
Ono
Makiko
M
Kouno
Tsutomu
T
Katsumata
Noriyuki
N
Ando
Masashi
M
Tamura
Kenji
K
Hasegawa
Tadashi
T
Kinoshita
Takayuki
T
Fujiwara
Yasuhiro
Y
D000328:Adult; D000368:Aged; D000911:Antibodies, Monoclonal / Q000008:administration & dosage*; D061067:Antibodies, Monoclonal, Humanized; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001943:Breast Neoplasms / Q000737:chemistry / Q000188:drug therapy*; D017024:Chemotherapy, Adjuvant; D066246:ErbB Receptors / Q000032:analysis*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D008875:Middle Aged; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000032:analysis* / Q000037:antagonists & inhibitors; D020893:Receptor, ErbB-3 / Q000032:analysis*; D066247:Receptor, ErbB-4; D000068878:Trastuzumab
D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D066246:ErbB Receptors; D018719:Erb-b2 Receptor Tyrosine Kinases; D020893:Receptor, ErbB-3; D066247:Receptor, ErbB-4; D000068878:Trastuzumab; C512478:EGFR protein, human; C508053:ERBB2 protein, human; C587689:ERBB4 protein, human