Breast calcifications

Breast calcifications are deposits of calcium in the breast tissue. They are quite common and most are not associated with cancer. They are not related to the amount of calcium that you take in through your diet or supplements.

Breast calcifications are often found during a screening mammography. They appear as white spots on the mammogram. Doctors will look at the size, shape and pattern of the calcifications. They may want to follow up on certain characteristics of a calcification, such as an irregular shape or how many calcifications are in an area of the breast.


Macrocalcifications are large, coarse calcium deposits in the breast. They are fairly common in women over the age of 50. They are often related to non-cancerous (benign) changes in the breast caused by:

  • aging of the arteries
  • injury to breast tissue, such as from a car accident
  • previous breast cancer treatments, including surgery or radiation therapy
  • infection in the breast tissues (called mastitis)
  • non-cancerous growths in the breast, such as fibroadenoma or cysts
  • calcium deposits in the skin or blood vessels

Doctors can easily identify macrocalcifications on a mammography and usually don’t need to do a biopsy to confirm the diagnosis.


Microcalcifications are tiny calcium deposits in the breast. Sometimes one microcalcification develops, or many microcalcifications (called a cluster) can develop in one area of a breast.

When breast cells grow and divide, they make more calcium. As a result, microcalcifications often develop in an area of the breast where cells are growing and dividing. When cells are more active in a certain area of the breast, it may mean that there are cancer cells in that area. Doctors may investigate a cluster of microcalcifications, but having microcalcifications does not mean that you have cancer.

If you have microcalcifications, your doctor may order:

  • diagnostic mammography with spot compression
  • a biopsy
  • another mammography in 6 months

Expert review and references

  • American Cancer Society. Breast Cancer. 2015:
  • Demetri-Lewis A, Slanetz PJ, Eisenberg RL . Breast calcifications: the focal group. AJR: American Journal of Roentgenology. 2012:
  • Macmillan Cancer Support. Breast calcifications. 2014.
  • Smithuis R & Pijnappel R . Breast calcifications - differential diagnosis and BIRADS. Radiology Assistant. 2008.

Medical disclaimer

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