Risk Factors
  • Age – Risk of developing breast cancer increases with age. The majority of breast cancer cases occur in women over 50.
  • Menstrual Periods – Women who started menstruating at an early age (before age 12) or who went through menopause at a late age (after age 55) have a slightly higher risk of breast cancer.
  • Not Having Children (or Having Them Later in Life) – Women who have had no children or who had their first child after age 30 have a slightly higher breast cancer risk.
  • Genetic Risk Factors – The most common inherited mutations are those of the BRCA 1 and 2 genes. Other genes have also been discovered.
  • Family History of Breast Cancer – Having one first-degree relative (mother, daughter, sister) with breast cancer approximately doubles a woman’s risk.
  • Personal History of Breast Cancer – A woman with cancer in one breast has a three– to fourfold increased risk of developing a new breast cancer.
  • Previous Radiation Therapy to Chest – Women who, as children or young adults, had radiation therapy to the chest area as treatment for another cancer (such as Hodgkin’s disease) are at significantly increased risk.
  • Oral Contraceptive Use – Studies suggest that women taking oral contraceptives have a slightly increased risk.
  • Postmenopausal Hormone Therapy – Long-term use (several years or more) of combined postmenopausal hormone therapy increases the risk of breast cancer.
  • Alcohol Use – Use of alcohol is clearly linked to an increased risk of developing breast cancer. The risk increases with the amount of alcohol consumed.
  • Overweight/Obesity – Being overweight or obese has been found to increase breast cancer risk, especially for women after menopause.
  • Physical Inactivity – Evidence is growing that physical activity in the form of exercise reduces breast cancer risk.
Breast Cancer Risk Assessment Tools

Several different programs and interactive tools are available for calculating a woman’s breast cancer risk. Each of the risk models listed below can be used for the purpose of identifying patients who would benefit from breast MRI screening. A woman with a lifetime risk greater than 20 percent should have an annual breast MRI.