Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2009 Jan 27;100(2):421-5.
doi: 10.1038/sj.bjc.6604830. Epub 2008 Dec 16.

Breast cancer risks in women with a family history of breast or ovarian cancer who have tested negative for a BRCA1 or BRCA2 mutation

Affiliations

Breast cancer risks in women with a family history of breast or ovarian cancer who have tested negative for a BRCA1 or BRCA2 mutation

K A Metcalfe et al. Br J Cancer. .

Abstract

Genetic testing for mutations in BRCA1 and BRCA2 is available in Canada for women with a significant family history of breast cancer. For the majority of tested women, a BRCA1 or BRCA2 mutation is not found, and counselling regarding breast cancer risk is based on the review of the pedigree. In this prospective study, we estimate breast cancer risks in women with a family history of breast cancer and for whom the proband tested negative for a mutation in BRCA1 or BRCA2. Families with two or more breast cancers under the age of 50 years, or with three cases of breast cancer at any age, and who tested negative for a BRCA1 or BRCA2 mutation were identified. Follow-up information on cancer status was collected on all first-degree relatives of breast cancer cases. The standardised incidence ratios (SIRs) for breast cancer were calculated by dividing the observed numbers of breast cancer by the expected numbers of breast cancers, based on the rates in the provincial cancer registries. A total of 1492 women from 365 families were included in the analyses. The 1492 first-degree relatives of breast cancer cases contributed 9109 person-years of follow-up. Sixty-five women developed breast cancer, compared to 15.2 expected number (SIR=4.3). The SIR was highest for women under the age of 40 (SIR=14.9) years and decreased with increasing age. However, the absolute risk was higher for women between the age of 50 and 70 (1% per year) years than for women between 30 and 50 (0.4% per year) years of age. There was no elevated risk for ovarian, colon or any other form of cancer. Women with a significant family history of breast cancer (ie, two or more breast cancers under the age of 50 years, or three or more breast cancers at any age), but who test negative for BRCA mutations have approximately a four-fold risk of breast cancer. Women in these families may be candidates for tamoxifen chemoprevention and/or intensified breast screening with an MRI.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Cumulative incidence of breast cancer.

References

    1. Cancer, Collaborative Group on Hormonal Factors in Breast Cancer (CGoHFiB) (2001) Familial breast cancer: collaborative reanalysis of individual data from 52 epidemiological studies including 58 209 women with breast cancer and 101 986 women without the disease. The Lancet 358: 1389–1399 - PubMed
    1. Claus EB, Risch NJ, Thompson WD (1990) Age at onset as an indicator of familial risk of breast cancer. Am J Epidemiol 131: 961–972 - PubMed
    1. Fisher B, Costantino JP, Wickerham DL, Redmond CK, Kavanah M, Cronin WM, Vogel V, Robidoux A, Dimitrov N, Atkins J, Daly M, Wieand S, Tan-Chiu E, Ford L, Wolmark N, NSABBPI (1998) Tamoxifen for prevention of breast cancer: report of the National Surgical Adjuvant Breast and Bowel Project P-1 study. J Natl Cancer Inst 90: 1371–1388 - PubMed
    1. Gail MH (2008) Discriminatory accuracy from single-nucleotide polymorphisms in models to predict breast cancer risk. J Natl Cancer Inst 100: 1037–1041 - PMC - PubMed
    1. Kauff ND, Mitra N, Robson ME, Hurley KE, Chuai S, Goldfrank D, Wadsworth E, Lee J, Cigler T, Borgen PI, Norton L, Barakat RR, Offit K (2005) Risk of ovarian cancer in BRCA1 and BRCA2 mutation-negative hereditary breast cancer families. J Natl Cancer Inst 97: 1382–1384 - PubMed

Publication types

MeSH terms