Breast calcifications are small deposits of calcium in the breast tissue. They often show up in mammograms and are most common in women over 50. Breast calcifications are typically noncancerous, or benign. However, some forms can occasionally indicate breast cancer.

In this article, we look at the causes of breast calcifications, and we discuss what may happen if they show up on a screening test.

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Calcifications are small calcium deposits that develop in the breasts. They do not cause symptoms, and it is not possible for a doctor to diagnose them from a routine breast check.

Instead, they typically appear on a mammogram — an X-ray of the breasts — as white dots. Other breast scans, such as ultrasounds or MRI scans, do not show up calcifications.

Calcifications are more likely to develop after menopause.

Most breast calcifications are benign, but clusters of calcium deposits can suggest early breast cancer. Some research indicates that doctors recall 12.7 to 41.2% of women in screening programs with breast calcifications as the only warning sign of cancer.

While calcifications do not develop into cancer, they can suggest that an underlying process is occurring that may be connected to breast cancer.

Two types of breast calcifications can appear on mammograms — macrocalcifications and microcalcifications. Some women have a mix of both.


Macrocalcifications appear as large white dots that occur randomly throughout the breast tissue. They are greater than 0.5 millimeters (mm) in diameter.

Macrocalcifications are very common, and doctors usually consider them to be benign. As a result, people with macrocalcifications in the breast usually require no follow-up testing.


Microcalcifications appear as tiny white specks or grains. Many cases of microcalcifications are benign. However, if they have certain characteristics, they may indicate breast cancer.

Doctors usually regard microcalcifications as suspicious and in need of further investigation if they have the following characteristics:

  • They are less than 0.5 mm in diameter.
  • They occur in clusters in one area of the breast.
  • They differ in size and shape.

A cluster generally consists of five or more calcifications, although this number is not definitive. Loose clusters are more likely to be benign than compact clusters.

Calcifications outside the main breast tissue

Occasionally, a mammogram may show up calcifications outside of the main breast tissue. These may appear to be on the skin or inside the blood vessels.

Those on the skin may be due to deodorant or powder residue that causes white dots to appear on the X-ray results.

Once the radiologist confirms the location as being outside of the breast tissue itself, then these types of calcifications require no further testing.

Calcifications can occur in the breast tissue as a result of:

Any of the above factors can cause breast calcifications to develop. Other factors that increase risk include:

  • a personal history of breast cancer
  • a family history of breast cancer
  • a genetic predisposition to breast cancer, such as having a BRCA1 and BRCA2 mutation

Deodorant, lotions, or powders can show up as calcifications on a mammogram. For this reason, people should avoid applying any skin products before the screening.

Eating calcium-rich foods does not cause breast calcifications.

If calcifications appear on a mammogram, the radiologist will decide if further investigation is necessary. Generally, they do not consider macrocalcifications to be suspicious.

However, if large calcifications occur in clusters or alongside microcalcifications, the radiologist may advise further testing.

If they consider the calcifications to be suspicious, they may:

  • perform another mammogram to view the calcifications more closely
  • check prior mammogram images to look for changes in calcification characteristics
  • refer the case to a doctor

A doctor may:

  • review the X-ray images and radiology report
  • take a biopsy to test the breast tissue for signs of cancer
  • recommend a breast MRI scan
  • recommend screening every 6 months to check for changes to the calcifications

People who have a history of breast cancer or are at a high risk of cancer development should see their doctor if calcifications appear on a mammogram. A doctor will take these risk factors into account when deciding on further testing.

A breast biopsy involves removing a small piece of breast tissue to examine it closely.

The two types of biopsies to test breast calcifications are stereotactic core needle biopsy and surgical biopsy.

Stereotactic core needle biopsy

During a stereotactic core needle biopsy, the doctor will apply a local anesthetic to the breast. They will then make a small cut in the skin and insert a needle.

Using computer images, they will guide the needle to the area of tissue containing the calcifications.

They will then remove a small piece of this tissue and withdraw the needle from the skin.

Surgical biopsy

During a surgical biopsy, a surgeon will apply a local anesthetic to the skin. Sometimes, the person may need general anesthesia. The surgeon will remove the abnormal tissue sample and send it to a lab for examination under a microscope.

Doctors typically only perform a surgical biopsy if a core needle biopsy is unsuccessful or if the results are inconclusive.

Individuals should discuss any concerns about scarring, anesthesia, or recovery with their surgeon before undergoing a surgical biopsy.

Benign calcifications do not require any treatment. However, if the calcifications have links to another medical condition — such as mammary duct ectasia — then a doctor will provide the person with more information on the condition and the available treatments.

If the calcifications indicate breast cancer, then the person will require treatment to stop the spread of the cancer and kill the cancerous cells. The type of treatment a person will need depends on the type of breast cancer, its size and stage, and other factors.

Potential treatments for breast cancer include:

Breast calcifications can indicate early breast cancer, which highlights the importance of having regular screening mammograms. However, most calcifications are benign and do not need any follow-up investigations or treatment.

If a radiologist considers the calcifications to be suspicious, they will perform another mammogram and may recommend a biopsy.

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