Breast cancer screening and diagnosis

The two tests commonly used to screen for breast cancer are the mammogram and a clinical breast exam (CBE). If you are at higher risk of breast cancer, your doctor might want to use other tests too, such as a different type of mammogram or magnetic resonance imaging (MRI).

If a screening mammogram or CBE shows a breast change that could be cancer, additional tests are needed to learn more. Finding out about "abnormal" breast changes can be scary. Be sure to talk to your doctor about what tests you might need and what the test results mean.

Tests might include:

  • Diagnostic mammogram. Uses x-rays to take more detailed images of areas that look abnormal on a screening mammogram.
  • Ultrasound exam. Sound waves help your doctor see if a lump is solid (could be cancer) or filled with fluid (a fluid-filled sac that is not cancer).
  • Magnetic resonance imaging (MRI). Radio waves and a powerful magnet linked to a computer are used to create detailed pictures of areas inside the breast.
  • Breast biopsy. Fluid or tissue is removed from the breast and checked for cancer cells. A biopsy is the only test to find out if cells are cancer.

What is a mammogram?

A mammogram is a low-dose x-ray exam of the breasts to look for changes that are not normal. The results are recorded on x-ray film or directly into a computer for a doctor to examine.

A mammogram allows the doctor to have a closer look for changes in breast tissue that cannot be felt during a breast exam. It is used for women who have no breast complaints and for women who have breast symptoms, such as a change in the shape or size of a breast, a lump, nipple discharge, or pain. Breast changes occur in almost all women. Most of these changes are not cancer, but only a doctor can know for sure. Like any test, mammograms have both benefits and limitations. For example, some cancers can't be found by a mammogram, but they may be found in a clinical breast exam.

A digital mammogram also uses x-rays to produce an image of the breast, but instead of storing the image directly on film, the image is stored directly on a computer. The recorded image can be magnified for the doctor to take a closer look.

The National Cancer Institute recommends that:

  • Women 40 years and older should get a mammogram every 1 to 2 years.
  • Women who have had breast cancer or other breast problems or who have a family history of breast cancer might need to start getting mammograms before age 40, or they might need to get them more often. Talk to your doctor about when to start and how often you should have a mammogram.