Breast cancer screenings


Breast cancer screenings can help find breast cancer early, before you notice any symptoms. In many cases, finding breast cancer early makes it easier to treat or cure. But screenings also have risks, such as missing signs of cancer. When to start screenings may depend on your age and risk factors.


A mammogram is the most common type of screening. It is an x-ray of the breast using a special machine. This test is done in a hospital or clinic and only takes a few minutes. Mammograms can find tumors that are too small to feel.

Mammograms work best at finding breast cancer in women ages 50 to 74. For women younger than age 50, the screening can be helpful, but may miss some cancers. This may be because younger women have denser breast tissue, which makes it harder to spot cancer. It is not clear how well mammograms work at finding cancer in women age 75 and older.

Experts do not agree about when women should have mammograms.

  • The American Cancer Society (ACS) and many other groups recommend that women have a mammogram every year starting at age 40.
  • The U.S. Preventive Services Task Force (USPSTF) recommends that women at average risk for breast cancer have mammograms once every 2 years beginning at age 50.

Talk with your health care provider about the benefits and risks of mammograms. You and your provider can decide how often you should have a mammogram based on your health, risk factors, family history, and values.

Breast Exams

This is an exam to feel the breasts and underarms for lumps or unusual changes. Your provider may perform a clinical breast exam (CBE). You can also check your breasts on your own. This is called a breast self-exam (BSE). Doing self-exams may help you become more familiar with your breasts. This may make it easier to notice unusual breast changes.

Keep in mind that breast exams do not reduce the risk of dying from breast cancer. They also do not work as well as mammograms to find cancer. For this reason, you should not rely only on breast exams to screen for cancer.

Not all experts agree about when to have or start having breast exams. In fact, some groups do not recommend them at all. However, this does not mean you should not do or have breast exams. Some women prefer to have exams.

Talk with your provider about the benefits and risks of breast exams and if they are right for you.

MRI (Magnetic Resonance Imaging)

An MRI uses powerful magnets and radio waves to find signs of cancer. This screening is done only in women who have a high risk for breast cancer.

The ACS recommends that women at high risk for breast cancer should have an MRI along with a mammogram every year. You may have a high risk if you have:

  • A family history of breast cancer
  • Certain BRCA mutations
  • Certain genetic syndromes

It is not clear how well MRIs work to find breast cancer. Although MRIs find more breast cancers than mammograms, they are also more likely to show signs of cancer when there is no cancer. This is called a false-positive result. For women who have had cancer in one breast, MRIs can be very helpful for finding hidden tumors in the other breast.

Benefits and Risks of Screenings

When deciding when to start breast cancer screenings, talk with your provider about the benefits and risks.

Breast cancer screenings can help find breast cancer early. In many cases, this makes the breast cancer easier to treat.

Risks of screenings can include:

  • False-positive results. This occurs when a test shows cancer when there is none. This can lead to having more tests that also have risks. It can also cause anxiety. You may be more likely to have a false-positive result if you are younger, have a family history of breast cancer, have had breast biopsies in the past, or take hormones.
  • False-negative results. These are tests that come back normal even though there is cancer. Women who have false-negative results do not know they have breast cancer and delay treatment.
  • Exposure to radiation is a risk factor for breast cancer. Mammograms expose your breasts to radiation.
  • Overtreatment. Mammograms and MRIs may find slow-growing cancers. These are cancers that may not shorten your life. At this time, it is not possible to know which cancers will grow and spread, so when cancer is found it is usually treated. Treatment can cause serious side effects.

Experts continue to study which screenings work best. Recommendations vary, so you should talk with your provider about which screenings are right for you and how often you need them.


American Cancer Society. Breast Cancer: Early Detection. Updated 4/9/2015. Available at: Accessed July 17, 2015.

National Cancer Institute: PDQ Breast Cancer Screening. Bethesda, MD: National Cancer Institute. Last modified June 19, 2015. Available at: Accessed July 3, 2015.

National Cancer Institute. Risks of Breast Cancer Screening. March 2014. Last reviewed: April 13, 2015. Available at: Accessed July 7, 2015

U.S. Preventive Services Task Force. Screening for Breast Cancer. Available at: Accessed July 7, 2015.

Review date:
July 10, 2014
Reviewed by:
Christine Zhang, MD, Medical Oncologist, Fresno, CA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.
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