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Patient Education: Diseases Conditions Treatments & Procedures

Breast Cancer

Risk Assessment & Prevention

Most women who develop breast cancer have no risk factors other than simply being a woman and getting older (especially being over 50). Your doctor may ask you questions to see if you have an increased risk of breast cancer.

Risk Factors for Breast Cancer

  • Age
  • Family history of breast or ovarian cancer, especially if diagnosed at a young age(see below)
  • Personal history of breast cancer
  • A history of breast biopsies showing abnormal but non-cancerous cells
  • Radiation treatment to the chest area (for example, to treat Hodgkin lymphoma), especially before age 30
  • Having dense breast tissue
  • An above-average exposure to the hormone estrogen, which your body naturally produces, perhaps because you:
    • have never given birth or gave birth for the first time after age 30
    • began menstruating at a young age
    • reached menopause later than average
    • have taken hormone replacement therapy (estrogen plus progestin) for more than five years
  • Smoking
  • Increased alcohol consumption
  • Obesity

Family history of breast cancer
Most inherited forms of breast cancer are associated with two specific genes called BRCA1 and BRCA2. Normally, these genes help to stop cancer from growing. If a person inherits an abnormal mutated BRCA1 or BRCA2 gene from their parents, their chance of getting breast and ovarian cancer is increased.

  • About 10% of breast cancer is due to strong hereditary factors, such as inherited mutations in the genes BRCA1 and BRCA2.
  • Having this mutated gene puts a person at a greater risk of getting breast cancer.
  • Breast cancer that runs in the family is known as hereditary breast cancer.
  • Families with hereditary cancer usually have more than one relative with breast and/or ovarian cancer.
  • Also, family members often get cancer before the age of 50.

If you think you have more than two relatives diagnosed with breast cancer or if you have more than one relative diagnosed with breast cancer under age 50, you should discuss this with your doctor. They may refer you to the High Risk Breast Cancer Clinic to help you assess your risk of hereditary breast cancer. A genetic counselor will discuss your eligibility for genetic testing with you at length.

Women at increased risk of breast cancer
Women who have an increased risk of breast cancer will be counseled by a physician in the program about cancer risk reduction strategies, including the role of preventive surgery, increased screening tests, taking a medication to reduce risk, and lifestyle factors.

Reducing breast cancer risk

Your Nutrition Connection, a publication by the Odette Cancer Centre and Ryerson University, explains how to minimize lifestyle factors that contribute to increased breast cancer risk.

Visit the Breast Care Group at Odette Cancer Centre