Your Test: Breast Cancer Screening

Mammogram.

Breast cancer happens when cells that are not normal grow in one or both of your breasts. These cells can form a tumor, and they may spread to other parts of your body.

Having concerns about breast cancer is normal. But experts have made great progress in treating it.

Why is screening for breast cancer important?

Screening, or testing, for breast cancer helps find problems early.

The earlier breast cancer is found, the more easily and successfully it can be treated. Sometimes the cancer can be treated without removing the breast. But finding breast cancer early doesn't always mean that it can be cured.

How is breast cancer screening done?

Several tests can be used to check for breast cancer. Women who are at average risk for breast cancer are usually screened with mammograms. If your risk for breast cancer is high, your doctor may talk with you about other types of tests, such as an MRI. Go to www.cancer.gov/bcrisktool to find out your personal risk level for breast cancer.

  • Mammograms check for signs of cancer using X-rays. They can show tumors that are too small for you or your doctor to feel.
    • Digital mammograms put images of the breast into an electronic file. This is the most common test to check for breast cancer.
    • Standard mammograms put images of the breast on film. This test is used less often than digital mammograms.
  • Clinical breast exam is a doctor's exam of the breast. Your doctor does a clinical breast exam by carefully feeling your breasts and under your arms to check for lumps or other changes.
  • MRI (magnetic resonance imaging) of the breast may be used as a screening test if you have a high risk of breast cancer.

Your doctor or breast cancer screening center may offer you other tests, such as digital breast tomosynthesis (also called 3D mammograms) or an abbreviated breast MRI (sometimes called a "fast MRI"). Talk to your doctor about whether these tests are right for you.

Learn what your breasts normally look and feel like. When you know what is normal for you, you are better able to notice changes.

Tell your doctor right away if you notice any changes in your breasts.

When should you get screened?

Ask your doctor how often you should be tested for breast cancer. How often you get tested and the kind of tests you get will depend on your age and your risk.

The guidelines that follow are for women who have an average risk for breast cancer. If you have a higher risk for breast cancer, such as having a family history of breast cancer in multiple relatives or at a young age, your doctor may recommend different guidelines for you.

Guidelines for women at an average risk

  • Ages 20 to 39: Some experts recommend that women have a clinical breast exam every 3 years, starting at age 20. Ask your doctor how often you should have this test. If you have a high risk for breast cancer, talk to your doctor about when to start yearly mammograms and other screening tests, such as MRI.
  • Ages 40 and older: Talk with your doctor about how often you should have mammograms and clinical breast exams. Experts differ on their recommendations.

What are the risks of screening?

Screening tests can sometimes give false results.

A false negative means that a screening test misses the cancer. This may suggest that you don't have cancer when in fact you do.

A false positive means that the test shows results that are not normal or are thought to be cancer, but there is no cancer. This could cause you to worry and to have unneeded tests or treatments, such as getting a lump removed from your breast.

Other risks

Some localized cancers found with screening may never cause symptoms or become life-threatening. Treatment for these cancers may not help you live longer, and it may cause side effects. Doctors have not yet found a way to identify which cancers have no risk of spreading.

Mammograms expose the breasts to a very low dose of radiation, but the risk of harm from this is small.

Talk to your doctor about the benefits and risks of screening.

Do you have any questions or concerns after reading this information? It's a good idea to write them down and take them to your next doctor visit.