Diagnostic vs. Screening Mammograms: Understanding the Difference

Breast screening is an important part of a woman’s self-care regimen. Regular breast screening helps identify the earliest signs and symptoms of breast cancer, at the time when it’s most treatable.

Even though you may not worry about breast cancer or think that you’re low risk, out of every eight women in the United States, one will develop breast cancer by age 75. Breast screening also helps doctors identify problems in your breast that aren’t related to cancer.

Mammograms are the gold-standard screening test for breast cancer. These simple, noninvasive (though awkward) tests can be lifesavers.

The American College of Gynecologists (ACOG) recommends that women at average risk of breast cancer get a screening mammogram every 1-2 years, starting at age 40. You may need to start earlier or have annual mammograms if your risk is increased by factors such as:

• Dense breast tissue
• Never having had children
• Having first child after age 30
• Starting your period before age 12 
• Starting menopause after age 55
• Having BRCA1 and BRCA2 gene mutations
• Personal history of breast cancer or breast disease
• Family history of breast or ovarian cancer
• Prior treatment with radiation therapy
• Exposure to the drug diethylstilbestrol (DES)

Smokers, shift workers, and women exposed to environmental toxins may also have an increased risk.

At Mass Medical Imaging in Lake Forest, Illinois, our expert doctors Joseph Calandra, MD and Karen Mass, MD recommend regular screening mammograms starting at age 40 or earlier, depending on your risk. In certain circumstances, we may also recommend a follow-up diagnostic mammogram.

But what’s the difference between a screening mammogram and a diagnostic mammogram? Why would anyone need both?

Screening mammogram

A screening mammogram is a type of X-ray that allows us to see inside each of your breasts from the front and from the side. A mammogram can be slightly uncomfortable and extremely awkward, but they’re completely noninvasive.

We recommend regular screening mammograms to be sure that your breasts are healthy. Not only do screening mammograms allow us to see breast cancers, even in their very early stages; they also let us know if you may have other breast issues that need attention.

Studies suggest that women who undergo regular mammograms and do develop cancer have better survival rates than those with cancer who didn’t have a mammogram. This relationship becomes even stronger with age.

In mammograms, cancers appear white against the darkness of fatty breast tissue. However, if you have dense, fibrous breast tissue, that also looks white on mammograms. If we notice areas that may be cancerous, or if your breast tissue is dense, which makes it harder to identify cancers, we recommend you for a diagnostic mammogram.

Diagnostic mammogram

When your doctor prescribes a diagnostic mammogram, that doesn’t mean you have cancer. It usually means we’ve seen suspicious regions in your breast or that your breast tissue is so dense that we can’t differentiate it from any potential cancers that could be there. Some women, such as those with breast implants, are always given a diagnostic mammogram.

Your doctor may also order a diagnostic mammogram if you present with signs or symptoms that could be an indication of breast cancer, such as:

• Nipple discharge
• Breast lump
• Change in size or shape of breast
• Thickened breast skin
• Changes in breast skin texture
• Breast pain

The procedure of a diagnostic mammogram is very similar to that of a screening mammogram. However, the technician takes more views of the breast for a diagnostic mammogram. If your doctor notices a suspicious area, the technician zooms in on that area for a closer look. 

If a suspicious area looks like cancer on a diagnostic mammogram, we may then perform a biopsy on that tissue. If the tissue is cancer-free, we schedule you for a follow-up mammogram in the future. If the tissue is cancerous, we refer you to an oncologist for treatment.

Is it time for your mammogram? Schedule a screening mammogram or diagnostic mammogram today by calling our friendly team or using our online appointment form.