Breast cancer is the second leading cause of death from cancer in women. A woman's lifetime risk of developing breast cancer is 12 percent (1 of every 8 women). Breast cancer risk is higher among women whose close blood relatives have this disease.

The University of Alabama's Dr. John McDonald offers some guidance on what women should know if breast cancer runs in their family.

  • According to the American Cancer Society, having one first-degree relative (mother, sister or daughter) with breast cancer approximately doubles a woman's risk; having two first-degree relatives increases her risk about three-fold. But less than 15 percent of women with breast cancer have a family member with this disease. This means that most (more than 85 percent) women who get breast cancer do not have a family history of this disease.
  • Early detection of breast cancer is important and affects a woman's long-term prognosis. Breast cancer screening includes (mammography, ultrasound and MRI), a clinical breast exam by a health-care professional and patient self-screening (breast self-exams and breast self-awareness).
  • Breast MRI is not recommended for screening women at average risk of developing breast cancer. However, the American Cancer Society does recommend enhanced screening (including breast MRI) for women with a 20 percent or greater lifetime risk of developing breast cancer, which includes the following: have a known BRCA 1 or 2 mutation; have a first-degree relative with a BRCA 1 or 2 mutation; a history of radiation therapy to the chest between the ages of 10 and 30; and other high-risk genetic syndromes. (BRCA 1 and 2 are human genes that produce tumor suppressor proteins. A harmful BRCA1 or 2 mutation can be inherited. A woman's of developing breast cancer is greatly increased if she inherits a harmful mutation in BRCA 1 or 2.)
  • Women in high-risk groups should be offered enhanced screening, which includes twice yearly clinical breast examinations by a health-care provider, annual mammography, annual breast MRI and instruction in breast self-examination.
  • If one or more of your relatives have had breast cancer, be sure to tell your doctor. If you are at risk, doctors will recommend starting screening earlier and using MRI scans, as well as mammograms. Screening can find earlier, when treatments are more likely to be successful.
  • Women should always report any changes in their breasts to their health-care provider as soon as possible for further evaluation.