Meaning of Breast Calcifications On Mammogram

Types and Patterns of Breast Calcifications and What This Means For You

Breast Calcifications on a Mammogram
Breast Calcifications on a Mammogram. National Cancer Institute

Breast calcifications are one of the findings that may be seen on your mammogram. They appear as white dots on your mammogram and may or may not be worrisome for breast cancer, depending on the type, pattern, and arrangement of the calcifications. 

Let's learn about the types of breast calcifications and what causes them. 

Types of Calcifications

There are two types of breast calcifications:

Macrocalcifications are large bits of calcium deposits found on a mammogram.

They may be due to natural changes in a woman's breast, like hardening of her breast arteries. Macrocalcifications may also represent areas of inflammation from an old injury or breast trauma. They are not usually linked to breast cancer.

According to the American Cancer Society, macrocalcifications occur in about 50 percent of women over the age of 50 and about 10 percent of women under the age of 50. 

Microcalcifications are tiny bits of calcium deposits that may be an early sign of breast cancer, although not always. The pattern of microcalcifications in a woman's breast tissue helps a radiologist decide whether breast cancer could be present. 

For example, eggshell or rim-like calcifications on a mammogram are usually benign, as are popcorn-like calcifications. Benign means that the calcifications are not due to cancer. Calcifications arranged in a loose cluster are also more likely to be benign.

On the other hand, linear rod-like calcifications are commonly seen in breast cancer, as are calcifications that vary in shape and size. Calcifications arranged in a tight cluster are also concerning for cancer. 

Benign (Non-Cancerous) Causes of Breast Calcifications:

  • old injury to breast tissue, natural wear and tear, prior breast surgery
  • mastitis or inflammation caused by a breast infection
  • calcium collected inside a dilated milk duct
  • calcium mixed with fluid in a benign breast cyst
  • powders, ointments or deodorants deposit calcium on the skin
  • radiation treatment for breast cancer
  • calcification in the arteries within your breast
  • calcifications in a fibroadenoma (benign growth)

What Happens Next, If You Have Microcalcifications?:

If your mammogram shows microcalcifications that are worrisome for breast cancer, a biopsy is recommended. A biopsy means that a small area of the suspicious breast tissue is removed and examined under a microscope for cancer cells. 

A biopsy is not always needed if there are microcalcifications — sometimes just close follow-up. 

It’s very important to do follow-up exams and tests to make sure that you get the best information on your health.


Andersen A, Etheridge N, Harridge S, & Llewelyn S. Calcification or artefact? A case study examining potential products which can mimic calcification in mammography. Breast Cancer Res. 2006;8(Suppl 1):P39. 

American Cancer Society. (2015). Mammograms and Other Breast Imaging Tests: What does the doctor look for on a mammogram? Retrieved October 12th, 2015.

Nalawade YV. Evaluation of breast calcifications. Indian J Radiol Imaging. 2009 Nov;19(4):282-86.

Yi A et al. Radiation-Induced Complications after Breast Cancer Radiation Therapy: a Pictorial Review of Multimodality Imaging Findings. Korean J Radiol. 2009 Sep-Oct;10(5):496-507.

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