Association between basal-like phenotype andBRCA1/2germline mutations in Korean breast cancer patients.
BACKGROUND
BRCAmutation testing allows index patients and their families to be provided with appropriate cancer risk-reduction strategies. Because of the low prevalence ofBRCAmutations in unselected breast cancer patients and the high cost of genetic testing, it is important to identify the subset of women who are likely to carryBRCAmutations. In the present study, we examined the association betweenBRCA1/2germline mutations and the immunohistochemical features of breast cancer.


METHODS
In a retrospective review of 498 breast cancer patients who had undergoneBRCAtesting at Seoul National University Bundang Hospital between July 2003 and September 2012, we gathered immunohistochemical information on estrogen receptor (er), progesterone receptor (pr), her2 (human epidermal growth factor receptor 2), cytokeratin 5/6, egfr (epidermal growth factor receptor), and p53 status.


RESULTS
Among the 411 patients eligible for the study, 50 (12.2%) had germline mutations inBRCA1orBRCA2. Of the 93 patients with triple-negative breast cancer (tnbc), 25 withBRCA1/2mutations were identified (BRCA1,20.4%;BRCA2,6.5%). On univariate analysis, er, pr, cytokeratin 5/6, egfr, and tnbc were found to be related toBRCA1mutations, but on multivariate analysis, only tnbc was significantly associated withBRCA1mutations. Among patients with early-onset breast cancer or with a family history of breast or ovarian cancer,BRCA1mutations were significantly more prevalent in the tnbc group than in the non-tnbc group.


CONCLUSIONS
In the present study, tnbc was the only independent predictor ofBRCA1mutation in patients at high risk of hereditary breast and ovarian cancers. Other histologic features of basal-like breast cancer did not improve the estimate ofBRCA1mutation risk.
Department of Surgery, Eulji University Hospital, Daejeon.
J
J
Jung
Department of Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam.
E
E
Kang
Department of Pathology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam.
J M
JM
Gwak
Department of Pathology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam.
A N
AN
Seo
Department of Pathology, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam.
S Y
SY
Park
Department of Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam.
A S
AS
Lee
Department of Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam.
H
H
Baek
Department of Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam.
S
S
Chae
Department of Surgery, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam.
E K
EK
Kim
Department of Surgery, Daerim St. Mary's Hospital, Seoul, Republic of Korea.
S W
SW
Kim
BRCA1; BRCA2; Basal-like phenotype; triple-negative breast cancer