Breast calcifications

Breast calcifications are small deposits of calcium in the breast. There are two types, macrocalcifications and microcalcifications.

In most cases, breast calcifications are harmless. They are usually picked up during a mammogram (breast x-ray).

Macrocalcifications are found in about half of all women over the age of 50. They are a natural result of breast ageing. They may be caused by calcium deposits in milk ducts, previous injuries or inflammation. They are not linked with cancer and don’t need any treatment.

Microcalcifications are not usually due to cancer. But can sometimes be a sign of pre-cancerous changes or early breast cancer if a group is found in one area. You may need further tests if these are found.

Tests may include a further, close-up mammogram and a breast biopsy. A breast biopsy is a type of test that checks if any cancer cells are present. A sample of breast tissue is collected using either a needle under local anaesthetic or a small operation.

What are breast calcifications?

Breast calcifications are small areas of calcium in the breast. You cannot feel them.

Breast calcifications usually show up on a breast x-ray (mammogram). Calcifications are very common, and in most cases they are harmless. There are two types.

Macrocalcifications (benign coarse calcifications)

These areas of calcium look like large white dots or dashes on a mammogram. Macrocalcifications are sometimes called benign coarse calcifications. They are a natural result of breast tissue ageing and are harmless. They are not linked with cancer and don't need any treatment or checking.

Macrocalcifications are found in about half of all women over the age of 50, and in about 1 in 10 (10%) younger women. They may be caused by calcium deposits in a cyst or in milk ducts as women get older, or as a result of previous injuries or inflammation. Calcium in the diet does not cause calcifications to form.


These 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.

Microcalcifications are not usually due to cancer. But a group of them in one area of the breast (a cluster) may sometimes be a sign of pre-cancerous changes or early breast cancer.

If calcifications are seen on a mammogram

If your mammogram shows that there are calcifications, a doctor who specialises in reading x-rays and scans (radiologist) will look at the size, shape and pattern of the calcifications. They will then decide if you need any further tests.

If only macrocalcifications are found, you won’t need any treatment or tests.

If microcalcifications are found, you will usually be asked to have a close-up mammogram of the affected area. If the results of this mammogram show the changes are clearly not cancer (benign), you won’t need to have any more tests.

If the results are not clear, your doctor will suggest you have a small sample of tissue taken (biopsy) for examination under a microscope. This gives your doctor more information to help them make an accurate diagnosis.

Breast biopsy

This is when the doctor removes a small piece of tissue or cells from a lump or abnormal area. A pathologist (doctor who specialises in analysing cells) examines the tissue or cells under a microscope to look for cancer cells.

There are different ways of taking a biopsy. Your doctor or nurse will explain the type you will have. You will have your breast biopsy done in the breast clinic or an x-ray department.

Before the biopsy is taken, the doctor will numb the area where the tissue is to be removed with local anaesthetic. You may feel some discomfort or pressure during the biopsy but only for a short time.

Your breast may be bruised and feel sore for a few days afterwards. You can take painkillers until this eases off and any bruising should go away within a couple of weeks.

Needle (core) biopsy

Your doctor will gently put a needle into the area of calcification to remove a small piece of tissue. They will do this using an ultrasound or a mammogram. This shows pictures of the breast and helps the doctor guide the biopsy needle to the affected area.

Vacuum-assisted biopsy (VAB)

Your doctor will give you an injection of local anaesthetic into the skin to numb the area. They then make a small cut and insert a needle through it into the breast. A mammogram or ultrasound picture helps them guide the needle to the correct area. The doctor uses a vacuum to gently withdraw a piece of breast tissue into a small collecting chamber. They can take several biopsies without needing to remove the needle and put it in again.

Wire guided biopsy

Your doctors may suggest you have this if they weren’t able to remove enough breast tissue with a needle biopsy or if the biopsy result is not clear. The doctor uses an x-ray or ultrasound to guide a fine wire into the breast to mark exactly where the surgeon should take the biopsy. The wire is kept in place with a dressing. You will have a small operation and the surgeon will remove the area of calcification. You may have this done under a general or local anaesthetic.

Biopsy results

Following a biopsy, most microcalcifications are shown to be non-cancerous (benign). If this is the case, you won’t need any treatment.

If there are cancer cells, it is usually a non-invasive breast cancer called ductal carcinoma in situ (DCIS), or a very small, early breast cancer. These can both be treated very successfully.

Your feelings

It’s natural to feel worried if you’re told you have breast calcifications and need further tests. But it’s important to remember most breast calcifications are not a sign of cancer.

If the biopsy results show that there is an early breast cancer, a surgeon or breast care nurse will explain more about this. They will talk to you about the treatment you need and give you support to help you cope.

If you have any concerns, talk to the doctor or breast nurse at the clinic. You can also talk to one of our cancer support specialists.

Back to Pre-cancerous conditions

Lobular carcinoma in situ (LCIS)

Women with Lobular carcinoma in situ (LCIS) should have regular breast screening. LCIS is not a cancer, but indicates a risk of cancer in later life.