Types of mammograms

Screening mammograms look for signs of cancer

Screening mammogram are x-ray exams of the breasts that are used for women who have no breast symptoms. The goal of a screening mammogram is to find breast cancer when it’s too small to be felt by a woman or her doctor. Finding small breast cancers early (before they have grown and spread) with a screening mammogram greatly improves a woman’s chance for successful treatment.

A screening mammogram usually takes 2 x-ray pictures (views) of each breast. Some women, such as those with large breasts, may need to have more pictures to see as much breast tissue as possible.

Diagnostic mammograms investigate possible problems

A woman with a breast problem (for instance, a lump or nipple discharge) or an abnormal area found in a screening mammogram typically gets a diagnostic mammogram. It’s still an x-ray exam of the breast, but it’s done for a different purpose.

During a diagnostic mammogram, additional pictures are taken to carefully study the area of concern. In most cases, special pictures are enlarged to make a small area of suspicious breast tissue bigger and easier to evaluate. Other types of x-ray pictures can be done, too, depending on the type of problem and where it is in the breast.

A diagnostic mammogram may offer a closer look and show that an area that looked abnormal on a screening mammogram is actually normal. When this happens, the woman goes back to routine yearly screening.

A diagnostic mammogram could also show that an area of abnormal tissue probably is not cancer, but the radiologist may not be ready to say that the area is normal based on these pictures alone. When this happens it’s common to ask the woman to return to be re-checked, usually in 4 to 6 months.

The results of the diagnostic work-up may suggest that a biopsy is needed to find out if the abnormal area is cancer. If your doctor recommends a biopsy, it does not mean that you have cancer. About 80% of all breast changes that are biopsied are found to be benign (not cancer). If a biopsy is needed, you should discuss the different types of biopsy with your doctor to decide which type is best for you.