Normal and Abnormal Mammogram Images

What Shading May (or May Not) Indicate

Regular mammograms are an important part of breast health. It's good to be familiar with how the images look in case a healthcare provider shows one to you.

A mammogram image has a black background and shows the breast in variations of gray and white. In general, the denser the tissue, the whiter it appears. This may include normal tissue and glands, as well as areas of benign (noncancerous) breast changes (such as fibroadenomas) and disease (breast cancer). Fat and other less-dense tissue look gray on a mammogram image.

Mammograms look different for each person: What matters most is what's normal for you. If you have dense breasts, your mammograms will have more white, and the radiologist will read them accordingly, watching for changes.

Read on to see some images of what mammograms may look like, and what reports you might read.

Normal Breast Tissue

Normal Fatty Breast Tissue
National Cancer Institute

This image is a mammogram of a normal fatty breast, typical of older women, that does not have a lot of dense tissue. A mammogram searching for abnormal lesions, benign lumps, or breast cancer is more accurate when performed on women with non-dense breasts such as these.

The gray areas correspond to normal fatty tissue, while the white areas are normal breast tissue with ducts and lobes. While breast masses also appear white on a mammogram, their color is typically more concentrated because they are denser than other features of a normal breast, like those seen here.

Most women will have their first mammogram around the age of 40, and this can serve as a good baseline from which to compare your images in the future. Women with breast cancer risk factors may start screening earlier.

Having a baseline mammogram, regardless of the frequency of your mammograms, is helpful in establishing what normal looks like for you. Over time, a woman's breasts can change. This can happen after childbirth, following a breast biopsy, or with breast implants. It is not uncommon to get benign lumps, cysts, masses, calcifications, or denser tissue.

Normal Dense Breast Tissue

Normal Dense Breast Tissue
National Cancer Institute

This image shows two mammograms of normal, dense breasts. As with the first image, the dark areas are fatty tissue, and the light areas are denser tissue that contains ducts, lobes, and other features. Compare these images and you can see the differences in density in what are both normal breasts.

Young women, especially those who have not had children, usually have dense and rather firm breast tissue. Mammogram images like these can be difficult for a radiologist to read because there is less differentiation between normal and possibly abnormal tissue, potentially hiding areas that need closer study.

Mammography equipment can be adjusted to image dense breasts, but that may not be enough to solve the problem. If a particular area needs a better image, a breast ultrasound is usually the next step. A breast MRI (magnetic resonance imaging) may be recommended for young women with a strong family history of breast cancer or those known to have genetic mutations that increase risk (see below).

Dense breasts are identified as such based on their appearance on a mammogram—not what they feel like. Having dense breasts is not abnormal. It just means you have less fat in your breasts than is typical. However, women with dense breasts do have a slightly higher risk of developing breast cancer.

Breast Calcifications

Breast Calcifications on a Mammogram
National Cancer Institute

Here, the lighter white areas show denser tissues, but the more concentrated white spots are calcifications. These are tiny bits of calcium that may show up in clusters or in patterns (like circles) along the milk ducts.

Calcifications are associated with extra cell activity in breast tissue. Usually, the extra cell growth is not cancerous. Sometimes, however, tight clusters of microcalcifications (small calcifications) can be an early warning sign of precancerous cells. Scattered microcalcifications are usually a sign of benign breast tissue.

The pattern and shape of microcalcifications can also give radiologists clues about whether cancer may be present. Fine, linear calcifications raise suspicion of underlying breast cancer, whereas popcorn, eggshell, and rim-like calcifications are usually benign.

In this mammogram image, the breast calcifications are in ductal patterns. This is considered an abnormal mammogram, but it's not necessarily one that indicates cancer. In this case, the woman was advised to have a follow-up mammogram in three months for comparison. If the woman had a lump associated with these calcifications, immediate further testing would have been needed.

Macrocalcifications (large calcifications) are larger bits of calcium due to the normal process of aging in the breasts. They are found in roughly half of women over the age of 50, and unlike microcalcifications, are not usually a sign of cancer.

Fibrocystic Breast Tissue

Fibrocystic Breast Tissue
National Cancer Institute

Fibroadenomas and cysts are benign breast masses that can appear in fibrocystic breast tissue. These can occur alone or in groups and show up on mammograms as a dense (white) mass.

This mammogram highlights thickened areas that are typical of fibrocystic changes. You can also identify some ducts by the patterns they form.

Normal fibrocystic changes in the breast can be affected by monthly hormonal fluctuations that may taper off in menopause. About half of all women experience fibrocystic changes in their breasts, especially during their fertile years.

Fibrocystic changes in the breast are usually not a sign of disease and do not require treatment. These changes can sometimes cause breast pain and lumpiness, so if this becomes concerning, see your healthcare provider.

If an abnormality is thought to be a cyst, a breast ultrasound is usually done to confirm that it is a cyst rather than a solid nodule. If a breast cyst is causing symptoms, a radiologist can use ultrasound guidance to place a needle in the cyst and drain it.

Breast Tumor

Lateral mammogram of female breast with tumor
ksass / Getty Images

As with the others, this mammogram shows both normal fatty tissue (dark) and lighter areas of denser breast tissue. What's concerning here is the whitest area on the bottom right, which shows a cancerous (cancerous) tumor.

A cancerous tumor in the breast is composed of a mass of cancer cells that are growing in an abnormal, uncontrolled way. The tumor may invade surrounding tissue, or it may shed cells into the bloodstream or lymph system. If the tumor cells migrate beyond the original site and spread to other parts of the body, it is considered metastatic breast cancer.

It's important to note that even if a change looks very much like cancer on a mammogram, there are some benign breast changes that mimic breast cancer. When this occurs, further imaging—and most often, a biopsy (removing a sample of tissue for examination in a lab)—are necessary to know whether it is truly cancer or not.

Likewise, a mammogram may appear normal even if cancer is present. Roughly 20% of breast cancers are not seen on a screening mammogram, and this number may be higher for women who have very dense breasts. In addition, some types of breast cancer, such as inflammatory breast cancer and Paget's disease of the breast, do not usually result in a mass and can easily be overlooked on a mammogram.

A confirmed breast tumor usually requires treatment by surgery and may require chemotherapy, radiation, targeted biological therapy, and/or hormonal therapy. When a breast tumor is found in an early stage of cancer, it is more likely to be successfully treated to prevent its spread or recurrence.

Breast Implant

Mammogram With Implants

Pam Stephan

This mammogram shows two views of a breast following a mastectomy and reconstruction with a silicone breast implant. (Mammograms can be performed on breast implants if less compression is used than what is required with natural breast tissue.) This woman had been successfully treated for a type of breast cancer called invasive ductal carcinoma.

In both views of this breast reconstruction, the implant appears as a light, smooth-sided area. This implant is inserted into a pocket of the chest wall. The chest wall muscle appears as the medium-dark area just outside the implant.

Mammograms taken after a diagnosis of breast cancer are important screening tests. There is no evidence of breast cancer in these images.

Note that the overhead view, called the cranial-caudal view, shows a smaller area than the diagonal view, called the mediolateral view. Having these two views is very helpful for healthcare providers to determine breast health.

Your Mammogram Report

Your mammogram report will detail the radiologist's opinion about what they reviewed, with notes on things like breast density, calcifications, or any masses.

If you are unsure of what any findings mean, talk to your healthcare provider.

In addition to noting any findings, you will see a BI-RADS number. BI-RADS stands for Breast Imaging Reporting and Data System, and the number is a classification of the likelihood your mammogram is normal or shows cancer.

If you have not had a biopsy, you will be assigned a number between 0 and 5. A score of 0 indicates that the mammogram didn't provide enough information to make a clear call. A score of 6 is given when a mass has already been found malignant.

Mammogram and MRI Image Comparisons

Mammogram and MRI Breast Images Comparison
National Cancer Institute

Mammograms, in addition to regular breast exams, are the primary screening tool used for breast cancer. Breast MRI is much more expensive than mammograms, and the equipment is not as widely available. For this reason, MRI technology is not used for routine breast screening.

However, breast MRI has its place. Because it can capture an image that is higher contrast and more detailed than a mammogram, it may be used for women who are at high risk for breast cancer or have dense breasts, or when a mammogram reveals an area that needs further examination. It is also often used, especially in younger women, to monitor the other breast for the development of breast cancer if a woman has had a mastectomy on one side.

These two side-by-side comparisons show mammography on the left and an MRI on the right. The MRI image illustrates the deeper level of detail, which is extremely helpful to confirm a diagnosis.

Summary

Mammogram images can be confusing, and it's not always clear what you're looking at. In general, dense tissue shows up white, and less dense tissue is grayer. Knowing what is normal for your breasts helps the technicians and radiologists determine what changes have occurred since your last mammogram, and if there are any new areas that need further examination.

A Word From Verywell

Mammogram images can be helpful along with other test results in the early diagnosis of breast cancer and may find cancers that can't be felt yet. Keep the limitations of mammograms in mind and talk with your healthcare provider about additional testing if you are concerned about their accuracy or your risk.

Frequently Asked Questions

  • What are abnormalities that can be detected on a mammogram?

    Abnormalities that may be seen on a mammogram can include calcifications or masses (these can be noncancerous, like cysts, or cancerous tumors), and abnormal density. Mammograms are not perfect, and they may not detect everything, so some experts also recommend regular clinical breast exams.

  • What is the next step after an abnormal mammogram?

    The next step is usually a diagnostic mammogram. This means another mammogram is done, but with more pictures of the area of interest so it can be further studied. You may also have a breast ultrasound or a breast MRI.

  • Can a radiologist tell you the results of your mammogram?

    It depends. Imaging centers have different policies, and your healthcare provider may want to go over the report with you. The radiologist will also write up the imaging report and you will be contacted with the results. If you get anxious waiting for the results, talk with your provider to see what can be done to speed them up.

  • Do you find out mammogram results right away?

    This can depend on whether it is a screening mammogram or diagnostic mammogram, whether there is a radiologist on-site, and the imaging center's specific guidelines. It may also depend on your health history and if the mammogram is looking for something specific. Talk with the healthcare provider who ordered the test to find out when you can expect results.

8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. American Cancer Society. Breast density and your mammogram report.

  2. Cleveland Clinic. Benign breast disease: Lump in the breast.

  3. Evans A, Trimboli RM, Athanasiou A, et al. Breast ultrasound: recommendations for information to women and referring physicians by the European Society of Breast ImagingInsights Imaging. 2018:9:449–461. doi:10.1007/s13244-018-0636-z

  4. Wilkinson L, Thomas V, Sharma N. Microcalcification on mammography: approaches to interpretation and biopsy. Br J Radiol. 2017;90(1069):20160594. doi:10.1259/bjr.20160594

  5. Bernal ACBA, Chaves GWOG, dos Santos Alves I, et al. Don't get scared but be aware: Focal fibrocystic changes. Clin Rev Cases. 2020;2(2):1-4.

  6. American Cancer Society. Limitations of mammograms.

  7. American Cancer Society. If you're called back after a mammogram.

  8. Breastcancer.org. Getting your test results. 2016.

Additional Reading
Originally written by
Pam Stephan
Pam Stephan is a breast cancer survivor.
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