Breast calcifications are calcium deposits within breast tissue. They appear as white spots or flecks on a mammogram.

Breast calcifications are common on mammograms, and they're especially prevalent after age 50. Although breast calcifications are usually noncancerous (benign), certain patterns of calcifications — such as tight clusters with irregular shapes and fine appearance — may indicate breast cancer or precancerous changes to breast tissue.

On a mammogram, breast calcifications can appear as macrocalcifications or microcalcifications.

• Macrocalcifications. These show up as large white dots or dashes. They're almost always noncancerous and require no further testing or follow-up.
• Microcalcifications. These show up as fine, white specks, similar to grains of salt. They're usually noncancerous, but certain patterns can be an early sign of cancer.

If breast calcifications appear suspicious on your initial mammogram, you will be called back for additional magnification views to get a closer look at the calcifications. If the second mammogram is still worrisome for cancer, your doctor may recommend a breast biopsy to know for sure. If the calcifications appear noncancerous, your doctor may recommend returning to your usual yearly screening or have you return in six months for a short-term follow-up to make sure the calcifications are not changing.