Breast calcifications

This information is about breast calcifications. It explains what breast calcifications are and how they are diagnosed.

What are breast calcifications?

Breast calcifications are small areas of calcium in the breast. They cannot be felt and can only be detected on a breast x-ray (mammogram). Calcifications are very common, and in most cases are harmless. There are two types:

Macro-calcifications are coarse calcium deposits in the breast. They look like large white dots or dashes on a mammogram. They are a natural result of breast aging and are found in about half of women over the age of 50 and in about one in ten younger women. They may be caused by calcium deposits in a cyst, or in milk ducts as women get older. They may also be the result of previous injuries or inflammation. Calcium in the diet does not cause calcifications.

Macro-calcifications are harmless. They are not linked with cancer and do not need any treatment or monitoring.

Micro-calcifications are tiny calcium deposits that show up as fine white specks on a mammogram. They are usually found in an area of the breast where cells are being replaced more quickly than normal. Usually, micro-calcifications are not due to cancer. However in a small number of cases, when a group of micro-calcifications are seen in one area (a cluster) it may be a sign of pre-cancerous changes in the breast or an early breast cancer.

What happens when calcifications are found on a mammogram?

If your mammogram shows that there are calcifications, a person who specialises in reading x-rays and scans (such as a radiologist) will look at the size, shape and pattern of calcifications to decide if any further tests or investigations are needed.

If macro-calcifications are found, no further treatment is needed.

If micro-calcifications are seen you will usually be asked to have a close-up mammogram (magnification views) of the affected area. Depending on the results of this, your doctor may recommend:

• no further action, as the changes are clearly not cancer
• a biopsy – taking a small sample of tissue from the area so that it can be looked at under a microscope.

Breast biopsy

When calcification is found, there is usually no lump in the breast to show where the calcification is. So the biopsy is taken using the following techniques:

Needle (core) biopsy using image guidance An ultrasound or a mammogram linked to a computer is used to produce detailed pictures (images) of the breast tissue. These images help the doctor to guide a needle to the area so that samples of the tissue can be taken. The needle biopsy is done under a local anaesthetic, which numbs the area. The tissue that has been removed is then x-rayed to confirm that the area of calcification has been biopsied successfully.

Needle or wire-localisation with surgical excision This is usually only done where a core needle biopsy has been unsuccessful at removing enough calcification or where the result is not clear. It is a two-stage procedure. Both stages usually take place on the same day but occasionally localisation may be carried out on the day before the operation.

Localisation: You will have a mammogram to show the position of the micro-calcifications within the breast. Local anaesthetic is then injected into that area of the breast to make it numb. A thin needle or wire is then placed into the area of micro-calcifications and kept in place with a dressing. 

Excision: Using the needle or wire as a guide the surgeon removes the area of tissue to be biopsied. This may be done under a general or a local anaesthetic.

What the biopsy might show

Most micro-calcifications are non-cancerous (benign).

However, if abnormal cells are detected, breast cancers discovered as a result of mammography tend to be non-invasive (DCIS) or small early breast cancers (breast cancer that has not spread).

Your feelings

When a woman is told she has breast calcifications her first reaction is often one of anxiety. Some women immediately think that they have cancer, so it is important to remember that most breast calcifications are benign and are not caused by cancer. If you have worries or concerns you may it find it helpful to discuss these with your doctor or specialist breast nurse at the clinic or to contact one of our specialist cancer nurses.

References

This section has been compiled using information from a number of reliable sources including;

• Diseases of the Breast (2nd edition). Harris et al. Lippincott-Raven, 2000.
• ABC of Breast Diseases (2nd edition). Dixon. BMJ, 2000

For further references, please see the general bibliography.