A risk factor is anything that increases your chance of developing a disease. Some risk factors are behavioural—you can eliminate or reduce them by creating new habits and making different lifestyle choices. Others are genetic or a combination of environmental and biomedical determinants. You are considered at risk for breast cancer if you meet the following criteria:
- A close blood relative (mother, sister, daughter) has had breast cancer.
- You have had breast cancer in the past.
- You have inherited abnormal genetic markers that indicate risk, particularly two abnormal genes: BRCA1 (BReast CAncer gene one) and BRCA2 (BReast CAncer gene two).
- You have dense breasts, which means you have a lot of fibrous or glandular tissue and not much fatty tissue in your breasts. Breast density has nothing to do with weight and can be determined through screening.
- You had your first child after age 30.
- You started menstruating early (before age 12) and / or started menopause later (after age 55).
- You are overweight.
- You drink alcohol.
- You have a sedentary lifestyle.
- You smoke.
Having a risk factor does not necessarily mean that you have or will get cancer. The most important thing is to be aware of risk factors and to inform your doctor if one or more apply to you.