How to Interpret Mammogram Results

After your mammogram, a radiologist will categorize your test results using a numbering system based on the likelihood of the presence of cancer. They will also classify breast density and calcifications.

Your healthcare provider may review these results and discuss them with you.

This article provides an overview of mammogram results, including Breast Imaging-Reporting and Data System (BI-RADS), breast density, calcifications, and recalls.

Woman with a doctor discussing mammogram results

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Breast Imaging-Reporting and Data System (BI-RADS)

BI-RADS is a standardized system for reporting mammogram findings. Standardization is essential because it allows healthcare providers to discuss results using the same terms, making confusion or miscommunication less likely.

BI-RADS categorizes findings using a 0–6 rating system. Each number represents a specific finding, including incomplete, negative, benign, probably benign, suspicious, highly suggestive of malignancy, and known biopsy-proved malignancy.

BI-RADS Categories
Number Meaning Explanation
 0 Incomplete You may need another mammogram or further tests, or the radiologist wants to compare current findings to older mammograms.
 1 Negative A typical test result; it means the radiologist found nothing abnormal.
 2 Benign This may be used instead of a 1 when a radiologist notes lumps or lymph nodes that are noncancerous.
 3 Probably benign There is a low chance of cancer; however, it warrants a close watch. You will likely need frequent, repeat mammograms to ensure the spot in question doesn't change over time (usually every six to 12 months for two years).
 4 Suspicious abnormality This finding usually recommends a biopsy. Within this category are levels from A-C: 4A means a low likelihood of cancer (2%–10%), 4B means a moderate likelihood of cancer (10%–50%), and 4C means a high likelihood of cancer (50%–95%).
 5 Highly suggestive of malignancy  This finding strongly recommends a biopsy for a high likelihood of cancer (greater than 95%). 
6 Known biopsy-proven malignancy This finding is used when there is an existing biopsy confirming cancer. This is usually used when a diagnosis has already been made, and the mammogram tracks treatment progress.

Breast Density

Mammograms also rate your breast density, which reflects the amount of fibrous and glandular tissue compared with fatty tissue. Your report will describe whether you have high- or low-density breast tissue.

Low-density (also called non-dense or fatty breasts) means that breast tissue is almost entirely fatty or that there are a few areas of density among the breasts. High-density breasts are evenly dense throughout or highly dense.

Dense breasts are common. About half of people over 40 who have breasts have dense breasts.

The Importance of Breast Density

Dense breasts have a higher risk of breast cancer. Dense breasts also make mammograms harder to read.

Calcifications

Calcifications on a mammogram are deposits of calcium in breast tissue. These are common and are not typically a sign of cancer or cause for concern.

Although it may seem logical that calcium in food or supplements would cause calcifications, that is not how breast calcium deposits occur. Instead, they can result from the following:

  • Calcium deposits in arteries in your breasts
  • Past breast infection or injury
  • Benign lumps or cysts

Macrocalcifications vs. Microcalcifications

Macrocalcifications are large, rounded calcifications that look like white spots on a mammogram. These are common in people over age 50 and are rarely cancerous. Often, no further testing is required for macrocalcifications.

Microcalcifications are tiny specs seen on a mammogram. These usually don't indicate cancer either; however, your healthcare provider may recommend further testing if they see this calcification.

What Is a Recall?

A recall means that the radiologist who reviewed your mammogram wants you to return for further testing. However, it does not mean you have breast cancer. Breast cancer diagnosis from a recall is uncommon, affecting less than 10% of people called back after a mammogram.

Recalls are more common for your first mammogram because the radiologist doesn't have another image for comparison. They are also more common in people who have not yet experienced menopause.

Recalls might occur when:

  • Pictures are unclear and need to be retaken.
  • There is evidence of calcification or mass.
  • An area of your breast looks different from the other areas.

Additional Tests

Further testing may mean a repeat mammogram or another imaging test. Recall testing may include:

If any of the imaging tests look suspicious, you will probably require a breast biopsy to evaluate the area in question under a microscope. A surgeon may perform a biopsy by extracting fluid with a needle or by surgically removing a lump or part of the breast tissue.

Summary

A main mammogram result component is BI-RADS, a number ranking system that describes a radiologist's findings. These results represent whether the appearance of the breast tissue looks normal, suspicious, or potentially cancerous. In addition, mammogram results include breast density, whether calcification was noted, and if so, what type. Sometimes, mammogram results also have a recall—a recommendation for further testing.

A Word From Verywell

Mammogram results, like other imaging test results, can be confusing. While gaining knowledge about the language and its meaning can be helpful, the best way to review results is with your healthcare provider. That way, they can answer your questions, alleviate your concerns, and offer recommendations for the next steps (if any are necessary).

Frequently Asked Questions

  • How accurate are mammograms?

    Like other screening tests, mammograms aren't 100% accurate. However, they are the best tool available to screen for breast cancer. Some limitations of mammograms are that they can result in false positives (resulting in unnecessary interventions) and false negatives (missing some cancers).

  • Why would you get called back after a mammogram?

    If your mammogram shows anything suspicious, your pictures are unclear, or some areas of your breast look different from other areas, you may be called back for further testing. Recalls are more common for first-time mammograms and people who have not yet gone through menopause.

  • Can you tell if you have breast cancer just based on a mammogram?

    Screening mammograms are not usually sufficient to diagnose cancer. Instead, a screening mammogram will identify whether your breast tissue looks normal or has suspicious areas that could indicate cancer. While a diagnostic mammogram may offer more detailed information, you will likely require a biopsy to confirm malignancy.

6 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. Understanding your mammogram report.

  2. Centers for Disease Control and Prevention. What does it mean to have dense breasts?.

  3. National Library of Medicine. Mammogram: Calcifications.

  4. American Cancer Society. Getting called back after a mammogram.

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

  6. American Cancer Society. Limitations of mammograms.

By Kathi Valeii
As a freelance writer, Kathi has experience writing both reported features and essays for national publications on the topics of healthcare, advocacy, and education. The bulk of her work centers on parenting, education, health, and social justice.