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A mammogram is an exam of the breasts used to detect cancer. Read this handout to learn about how the exam works, how to prepare for the exam, how the exam is performed, what to expect during the exam, and how you will get your results.

Mammography is a type of imaging that uses a low-dose X-ray system for a breast exam. The Breast Imaging Department has a state-of-the-art digital mammography system that makes mammograms faster and easier than ever before, while providing our doctors with highly detailed images to use in diagnosis.
Most medical experts agree that finding breast cancer early is linked to successful treatment. Mammography plays a central part in finding breast cancers early because it can show changes in the breast up to two years before a patient or doctor can feel them.

Current guidelines advise screening mammography every year for women, beginning at age 40.*

The National Cancer Institute (NCI) adds that women who have had breast cancer – and those at increased risk due to genetic history of breast cancer – should seek expert medical advice about whether or not they should begin screening before age 40 and how often they should have a screening.

*These guidelines were developed by the U.S. Department of Health and Human Services (HHS), the American Cancer Society (ACS), the American Medical Association (AMA) and the American College of Radiology (ACR).

How does the exam work?

The breast is exposed to a small dose of radiation to produce a picture of the inner breast tissue.

How should I prepare for the exam?

• Before setting a date for a mammogram, talk to your doctor about any new findings or problems in your breasts. Inform your doctor of any past surgeries, hormone use, and family or personal history of breast cancer.
  
• Do not schedule your mammogram for the week before your period if your breasts are often tender during this time. The best time is one week after your period. Tell your doctor or technologist if there is any chance you may be pregnant.
  
• Do not wear deodorant, talcum powder, or lotion under your arms or on your breasts on the day of the exam. These can appear on the film as calcium spots. 
  
• You will be given special wipes to cleanse your underarms and breast. 
  
• If you can, obtain past mammograms and give them to the radiologist at the time of the current exam. 
  
• Before the exam, you will be asked to remove all jewelry and clothing above the waist, and you will be given a gown or loose-fitting material that opens in the front.

How is the exam performed?

1. During mammography, a specially qualified technologist will position you to image your breast. The breast is first placed on a special platform and compressed with a paddle. Breast compression is done to:
   • Even out the breast so that all of the tissue can be seen. 
   • Spread out the tissue so that small abnormalities won't be hidden by overlying breast tissue. 
   • Allow the use of a lower X-ray dose since a thinner amount of breast tissue is being imaged. 
   • Hold the breast still to avoid blurring of the image caused by movement. 
   • Increase sharpness of the picture.
     
2. The technologist will go behind a shield while taking the X-ray picture, which will send a beam of X-rays through the breast to the film behind the plate, exposing the film.
   
3. You will be asked to change places slightly between pictures. The routine views are a top-to-bottom view and a side view. The process is repeated for the other breast.
   
4. The exam should take about 20 minutes. When the exam is done, you will be asked to wait until the technologist reviews the pictures to decide if more are needed.

What will I feel during the exam?

You will feel pressure on your breast as it is squeezed by the paddle. Some women with sensitive breasts may feel uncomfortable. If you have sensitive breasts, have the exam done when your breasts are least tender. The technologist will apply pressure gradually. Be sure to tell the technologist if you feel pain. If you are in a great deal of distress, less compression will be used.

Who interprets the results and how do I get them?

A radiologist trained in mammography will read your films and interpret the results. You will receive a letter with your results in the mail within 7 to 10 working days. Your health care provider will also receive a report and be able to answer your questions about your mammogram.

• If you have not received a letter with your results in the mail in 10 days, call our office at 206-288-7800.  You may receive a letter asking you to return for more mammogram views or for an ultrasound. Don’t be alarmed if this happens. Repeat testing is fairly common and only means that the radiologist would like a better look at some areas of your breast, or some pictures may need to be repeated because of technical factors.
  
• To schedule repeat testing, call 206-288-7800. The additional exams will be done at UW Breast Imaging Center at the Seattle Cancer Care Alliance on Lake Union for all patients who had their screening mammograms at UW Medicine Neighborhood clinics, UW Medical Center at Roosevelt clinics, Harborview Medical Center, and Seattle Cancer Care Alliance. The additional exams will be done by specially trained staff and will be reviewed by the on-site Breast Imaging Radiologist. The results of your exam will be discussed with you before you leave.