Many women receive a concerning phone call from their mammography center or physician about returning for additional imaging of tiny white spots called calcifications. Calcifications cannot be detected by touch but are frequently seen on mammograms, becoming more common as women get older, especially after menopause. Occasionally, they also occur in a man's breast tissue. There are two types of breast calcifications: macrocalcification and microcalcification. Macrocalcifications are large deposits (greater than 0.5 mm) and are usually not related to cancer (benign). The other type, microcalcifications, are specks of calcium (less than 0.5 mm) that may be found in an area of rapidly dividing cells. It’s this type that indicates precancerous conditions or even breast cancer.
Calcifications are usually non-cancerous changes in the breast tissue associated with aging, but there are various causes for calcifications. Your breast health provider will work to determine the cause of any breast calcification to determine whether more imaging or a biopsy should be done.
Common causes of breast calcification include:
Injury or infection of the breast. Injuries to the breast caused by falls or auto accidents could result in calcifications. Women who breastfeed their babies and experience a breast infection called mastitis could also develop breast calcifications. Women should tell their breast specialists about breast injuries and/or their history of mastitis.
Prior radiation for breast cancer or previous breast surgery. Radiation therapy or surgery on the breast sometimes causes scarring to the breast tissue. This scar tissue may sometimes calcify.
Blood vessel calcifications. Calcium build-up can occur in the breast's blood vessels just as it occurs in the heart, aorta, or leg blood vessels. This process is called atherosclerosis. A woman who has cardiovascular risk factors or knows she has cardiovascular disease may have these appear on her mammogram.
Breast cyst. A fluid-filled sac may occur in one or both breasts. Cysts are common and usually occur in women before the onset of menopause. Cysts also develop in postmenopausal women on hormone therapy. Cysts can be oval or round and usually feel like a grape or a balloon filled with water. They usually have smooth, distinct edges and may be tender to the touch. Sometimes, cysts become smaller after a woman's period. Occasionally (less than 5% of the time), a cyst can contain specks of milk of calcium crystals or floating cholesterol crystals, which may appear as calcifications in a mammogram.
Cell secretions. The glandular cells can produce calcium in the ducts.
Fibroadenoma. Fibroadenomas occur most often in young women, ages 15 to 35. These breast growths are benign — they are usually hard (feel like a marble), have a well-defined shape, and aren't painful. They also move quite easily beneath the skin and may shrink or grow. Smaller fibroadenomas are often discovered on a woman's first mammogram. Larger fibroadenomas that occur in younger women may be biopsied.
Mammary duct ectasia. During the time just before menopause, a woman's milk ducts may enlarge. The walls of the ducts may become thicker. The duct may develop fluid that can thicken and block the duct.
For some women, the calcifications found are an indicator of breast cancer starting to develop. This is called ductal carcinoma in situ (DCIS). DCIS means that cancer cells are located along the breast's milk duct's lining but have not spread. DCIS is called Stage 0 breast cancer. Higher-grade DCIS is more likely to result in breast calcifications. However, most calcifications are not cancerous.
What Do Breast Calcifications Mean?
Breast calcifications aren’t of huge concern for most women, but experts agree that the radiologist reading your mammogram should study the images to determine if your calcifications should be tested further with a biopsy or, at a minimum, additional images. For some women, there are symptoms of breast cancer.
Calcifications appear as small white dots. If the radiologist sees these dots, he looks at them to determine several characteristics:
Size – small or large.
Shape – round, irregularly shaped like popcorn or rod-like.
Pattern – randomly scattered or clustered.
If possible, the radiologist will compare your new mammogram to a previous one. Patients may be called back for a second mammogram, called a diagnostic mammogram. The second mammogram provides additional views of the suspicious areas. The radiologist then classifies the calcifications:
Suspicious abnormality or suggestive of cancer
If further imaging shows that the calcifications are an area of concern, additional testing is likely.
When Do Breast Calcifications Require Follow-Up Tests?
No follow-up or treatment will be needed if test results show macrocalcifications, as these larger breast calcifications are benign.
Microcalcifications, on the other hand, will need to be looked at more closely. Patients whose results show these smaller breast calcifications will need additional testing as these are suggestive of cancer.
Every patient is different, so not every patient requires the same additional testing. If additional tests for breast calcifications are needed, they could include the following:
Ultrasound or MRI (magnetic resonance imaging)
While a biopsy is scary, most women agree that they want to know if they have cancer to get it treated as quickly as possible.
Do Benign Calcifications Increase My Risk of Developing Breast Cancer?
Breast calcifications are pretty common — and the good news is that the majority of them are not cancerous.
Women who have had macrocalcifications (the larger calcifications) are not at increased risk for breast cancer. These larger calcifications are not associated with the development of breast cancer.
If microcalcifications occur in small lines or small clusters, a woman might be at increased risk of developing breast cancer. In these circumstances, the radiologist and her doctor recommend additional testing.
If biopsy results show no cancer, these small areas will be compared annually to detect changes. An additional biopsy is only needed when a new area of microcalcifications is detected or there's a change from a patient's previous mammogram.
Radiologists at breast cancer imaging centers don't want to cause unnecessary worry in patients. Still, they will err on the side of caution to ensure that early breast cancer is detected.
Careful use of new digital technology and the knowledge of which types of calcifications are linked to an increased risk of breast cancer offer women increased assurance that their breast cancer will be detected when it's most treatable.
It’s important to stay on schedule for your breast cancer screenings. Talk to your doctor by age 35 to see what screening schedule is right for you.