Significance of E-cadherin expression in triple-negative breast cancer.
OBJECTIVE
Triple-negative breast cancer (TNBC), a subtype of breast cancer that is oestrogen receptor (ER) negative, progesterone receptor (PR) negative, and human epidermal growth factor receptor 2 (HER2) negative, has a poor prognosis. Although a correlation between E-cadherin expression level and outcome has been demonstrated among all types of breast cancer, little is known about the significance of E-cadherin expression levels in TNBC.


METHODS
A total of 574 patients who had undergone a resection of a primary breast cancer except for invasive lobular carcinomas were enrolled in this study. Expressions of ER, PR, HER2, and E-cadherin were assessed by immunohistochemistry. We examined the association between TNBC and other clinicopathological variables and evaluated the significance of the E-cadherin expression.


RESULTS
Among the 574 breast cancer cases, 123 (21.4%) revealed a triple-negative phenotype. Patients with TNBC experienced more frequent lymph node metastasis (P=0.024) and a poorer prognosis (P<0.001) in comparison with non-TNBC patients. Triple-negative breast cancer was an independent prognostic factor. Reduced levels of E-cadherin were observed in 238 (41.5%) of the 574 breast cancer cases. E-cadherin reduction was significantly frequent in cases of TNBC (P<0.001) and lymph node metastasis (P=0.032). Furthermore, in the 123 TNBC cases, the prognosis of patients with an E-cadherin-negative expression was significantly worse than that of E-cadherin-positive patients (P=0.0265), especially for those in clinical stage II (P=0.002). A multivariate logistic regression analysis showed a reduction of the E-cadherin expression to be an independent prognostic factor (P=0.046).


CONCLUSIONS
E-cadherin expression may be a useful prognostic marker for classifying subgroups of TNBC.
Kashiwagi
S
S
Department of Surgical Oncology, Osaka City University Graduate School of Medicine, 1-4-3 Asahi-machi, Abeno-ku, Osaka, Japan.
Yashiro
M
M
Takashima
T
T
Nomura
S
S
Noda
S
S
Kawajiri
H
H
Ishikawa
T
T
Wakasa
K
K
Hirakawa
K
K
D001943:Breast Neoplasms / Q000378:metabolism* / Q000401:mortality / Q000473:pathology; D015820:Cadherins / Q000378:metabolism*; D066246:ErbB Receptors / Q000032:analysis; D006801:Humans; D008875:Middle Aged; D011379:Prognosis; D011960:Receptors, Estrogen / Q000032:analysis*; D011980:Receptors, Progesterone / Q000032:analysis
D015820:Cadherins; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D066246:ErbB Receptors