Preparing for Your Mammogram

Last Updated: Nov. 1, 2003

What is mammography?
Mammography is a specific type of imaging that uses a low-dose X-ray system and high-contrast, high-resolution film for examination of the breasts. Most medical experts agree that successful treatment of breast cancer often is linked to early diagnosis.

Mammography plays a central part in early detection of breast cancers because it can show changes in the breast up to two years before a patient or physician can feel them. Screening mammography is recommended every year for women beginning at age 40. The National Cancer Institute (NCI) adds that women who are at increased genetic risk due to a family history of breast cancer should seek expert medical advice about whether they should begin screening before age 40.

How should I prepare for my mammogram?
Before scheduling a mammogram, the American Cancer Society (ACS) and other specialty organizations recommend that you discuss any new findings or problems in your breasts with your doctor. In addition, inform your doctor of any prior 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 usually tender during this time. The best time is one week following your period. Always inform your doctor or X-ray technologist if there is any possibility that you are pregnant. Please inform the scheduler if you have breast implants, as the study will require more time to perform.

The ACS also recommends the following:

• Do not wear deodorant, talcum powder, or lotion under your arms on the day of the exam. These can appear on the X-ray film as calcium spots.
• Describe any breast symptoms or problems to the technologist performing the exam.
• If possible, obtain prior mammograms and make them available to the radiologist at the time of the current exam. Since normal breast appearance varies from woman to woman and the change in appearance caused by breast cancer may be very subtle, having the prior examinations available is very important for the radiologist interpreting your mammogram.

Please do not bring small children on the day of your examination. Children are not allowed in the mammography suite and may not be left unattended.

What should I expect at my mammogram appointment?
You should arrive 15 minutes before your scheduled appointment time. Before the examination, you will be asked to remove all jewelry and clothing above the waist and you will be given a gown that opens in the front. The mammography technologist will ask if you have a family or personal history of breast cancer, if you have any breast problems, and about your hormonal status. The technologist, who is specially trained in physical breast examination and specially qualified in breast imaging, will then examine your breasts for the presence of masses or skin abnormalities.

During mammography the technologist will position you to image your breast. She will place your breast on a special cassette and compress it gradually with a paddle made of clear, soft plastic. If compression is painful, let the technologist know, and less compression will be used. Recognize, however that adequate breast compression is essential to a good examination.

Breast compression is necessary to do the following:

• Even out the breast thickness so that all of the tissue can be visualized
• Spread out the tissue so that small abnormalities won't be obscured 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 in order to eliminate blurring of the image caused by motion
• Reduce X-ray scatter which also leads to poor image quality

The technologist will go behind a glass shield while making the X-ray exposure, which will send a beam of X-rays through the breast to the film behind the plate, thus exposing the film. She will then reposition you for the next view. The routine views are a top-to-bottom view and a side view of each breast for a total of four views. If you have exceptionally large breasts, additional views may be required to make sure that all of the breast tissue is imaged.

If you have breast implants, four views of each breast will be obtained. The examination process should take about half an hour (one hour for patients with implants). When the mammogram is completed the technologist will develop the films and assess their technical quality while you wait. Occasionally, more images may be taken at this point.

Who will interpret my mammogram, and how will I get the result?
A radiologist, who is a physician experienced in mammography and other X-ray examinations, will analyze the images, describe any abnormalities, and suggest a likely diagnosis. The report will be dictated by the radiologist, and then sent to your referring physician.

Why might I be called back for additional images?
Between 5% and 10% of mammogram results are indeterminate, resulting in the need for additional mammogram views or breast ultrasound. If these follow-up tests confirm that no cancer was present, which is most of the time, the initial examination is said to have been falsely positive.

It is estimated that a woman who has yearly mammograms between ages 40 and 49 has about a 30% chance of having a false-positive mammogram at some point in that decade, and about a 7% to 8% chance of having a breast biopsy within the 10-year period. The estimate for false-positive mammograms is about 25% for women ages 50 or older.

Source: Advanced Healthcare, S.C.

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