Genetic Disposition.

Although all women are at high risk for breast cancer, various studies have demonstrated that certain subgroups have a significantly increased probability of developing this disease compared to their same-age counterparts. In the early 1990s, two genes (BRCA1 and BRCA2) have been identified in which mutations are associated with an up to 85% lifetime risk for developing breast cancer. It is estimated that more than 50% of BRCA1 mutation carriers have already developed the disease by age 50 (Easton et al. 1995). In addition, BRCA1 and BRCA2 genes are associated with an increased risk for ovarian cancer. Other genetic predispositions for breast cancer might exist, but have not yet been discovered. Therefore, evaluation of family history for breast and ovarian cancer is of significant importance for the detection of individuals at moderate or high risk. Mammography is the current standard screening method for early diagnosis of breast cancer. However, women at high-risk tend to develop cancer at a younger age, when their tissue is more dense and the detection of small in-situ and invasive cancer is more challenging. [ABSTRACT FROM AUTHOR]