Research article

A family history of breast cancer will not predict female early onset breast cancer in a population-based setting

Geertruida H de Bock^1,2 , Catharina E Jacobi² , Caroline Seynaeve³ , Elly MM Krol-Warmerdam⁴ , Jannet Blom³ , Christi J van Asperen⁵ , Cees J Cornelisse⁶ , Jan GM Klijn³ , Peter Devilee⁷ , Rob AEM Tollenaar⁴ , Cecile TM Brekelmans³ and Johannes C van Houwelingen⁸

¹Department of Epidemiology, Groningen University Medical Center, Groningen, The Netherlands

²Department of Medical Decision Making, Leiden University Medical Center, Leiden, The Netherlands

³Department of Medical Oncology, Erasmus Medical Center-Dr Daniel den Hoed Cancer Center, Rotterdam, The Netherlands

⁴Department of Surgery, Leiden University Medical Center, Leiden, The Netherlands

⁵Department of Clinical Genetics, Leiden University Medical Center, Leiden, The Netherlands

⁶Department of Pathology, Leiden University Medical Center, Leiden, The Netherlands

⁷Department of Human Genetics, Leiden University Medical Center, Leiden, The Netherlands

⁸Department of Medical Statistics, Leiden University Medical Center, Leiden, The Netherlands

author email corresponding author email

BMC Cancer 2008, 8:203doi:10.1186/1471-2407-8-203

Published:	23 July 2008

Abstract

Background

An increased risk of breast cancer for relatives of breast cancer patients has been demonstrated in many studies, and having a relative diagnosed with breast cancer at an early age is an indication for breast cancer screening. This indication has been derived from estimates based on data from cancer-prone families or from BRCA1/2 mutation families, and might be biased because BRCA1/2 mutations explain only a small proportion of the familial clustering of breast cancer. The aim of the current study was to determine the predictive value of a family history of cancer with regard to early onset of female breast cancer in a population based setting.

Methods

An unselected sample of 1,987 women with and without breast cancer was studied with regard to the age of diagnosis of breast cancer.

Results

The risk of early-onset breast cancer was increased when there were: (1) at least 2 cases of female breast cancer in first-degree relatives (yes/no; HR at age 30: 3.09; 95% CI: 128-7.44), (2) at least 2 cases of female breast cancer in first or second-degree relatives under the age of 50 (yes/no; HR at age 30: 3.36; 95% CI: 1.12–10.08), (3) at least 1 case of female breast cancer under the age of 40 in a first- or second-degree relative (yes/no; HR at age 30: 2.06; 95% CI: 0.83–5.12) and (4) any case of bilateral breast cancer (yes/no; HR at age 30: 3.47; 95%: 1.33–9.05). The positive predictive value of having 2 or more of these characteristics was 13% for breast cancer before the age of 70, 11% for breast cancer before the age of 50, and 1% for breast cancer before the age of 30.

Conclusion

Applying family history related criteria in an unselected population could result in the screening of many women who will not develop breast cancer at an early age.