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The Basics About Breast Cancer Risk

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We all know someone who has been affected by breast cancer. While we don't yet know how to prevent it, there are some things we can do to reduce risk. Start with this page to discover the simple facts about breast cancer, cancer risk, and scientific research exploring those subjects.

What is Cancer?

Cancer is the uncontrolled spread and growth of abnormal cells.

Some people are born with abnormal cells. Sometimes, changes in cells happen later. Cancer can start anywhere in the body and is affected by a variety of things that go on for a long time both inside and outside our bodies.

What Are Risk Factors

Risk factors either increase or decrease the chance of getting cancer. Risk factors are not necessarily things that cause cancer.

A factor that is associated with cancer in one person may not be associated in another. Having one or more risk factors does not mean that you will get cancer. Even though some of the risk factors for breast cancer are identified, no one factor ever explains any given case of breast cancer.

Are There Any Known or Possible Risk Factors for Breast Cancer?

See our list.

Is There a Connection Between Breast Cancer Risk and Environment?

Because established risk factors for breast cancer account for less than half of all cases, scientists believe environment may play a role in this disease.

It is possible that early exposure to some environmental factors increases the risk for breast cancer later in life. Environment means everything except inherited factors, including: