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Breast calcifications

Breast calcifications are deposits of calcium in the breast tissue. These calcifications are not related to the amount of calcium that a person takes in through their diet or supplements.

Breast calcifications are quite common and are often found during a screening mammography. They appear as white spots on the mammogram. The radiologistradiologistThe use of imaging techniques (such as x-rays, CT scan or MRI) to study, diagnose and treat disease. looks at the size, shape and pattern of calcifications and reports these as part of the results of the mammography.

Most breast calcifications are not associated with cancer. However, certain characteristics of calcifications, such as irregular shapes or certain groupings, can be a concern.

There are 2 types of calcifications:


Macrocalcifications are larger, coarser calcium deposits in the breast. They are fairly common in women over the age of 50. They are often related to benign changes in the breast caused by:

  • aging of the breast arteries
  • injury to the breast tissues
    • car accidents
    • previous breast cancer treatments (including surgery or radiation therapy)
  • inflammation of the breast tissues (mastitis)
  • non-cancerous (benign) growths in the breast, such as:
  • calcium deposits in the skin or blood vessels

Macrocalcifications have very distinct appearances on mammography and are usually associated with benign conditions. Most macrocalcifications do not require a biopsybiopsyThe removal of cells or tissues for examination under a microscope..


Microcalcifications are tiny calcium deposits in the breast. They may suggest areas of increased activity in some breast cells. When these cells are more active, they take in more calcium from the body.

Microcalcifications can appear alone or in clusters (many in one area).They may indicate the presence of a small cancer like ductal carcinoma in situ (DCIS), but microcalcifications do not always mean that cancer is present.

If the microcalcifications look suspicious, the radiologist may suggest:

  • biopsy
  • diagnostic mammography with spot compression
  • repeat mammography in 6 months


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