Authors:  Dr Michelle Bennett*
                        A/Prof Liz Wylie*

What is a breast core biopsy?

A breast core biopsy is where a special needle is inserted into the breast to take a small sample of breast tissue from an area of concern, so that it can be sent to a laboratory for testing.

If a lump in the breast can be felt, then the core biopsy will sometimes be done in a surgical consulting room. If an abnormality in the breast cannot be felt as a lump, a radiologist or other specialist doctor carrying out the biopsy will use ultrasound or breast X-ray images or pictures (mammograms) to ensure the needle is placed exactly in the correct position. Occasionally, the doctor may position the needle with the help of images taken with a magnetic resonance imaging machine. Once the needle is in the correct position, several small tissue samples are taken from the area where the abnormality has been identified.

Why would my doctor refer me to have this procedure?

You may be referred for a needle biopsy under the following circumstances:

  • If you or your doctor can feel a lump in the breast and an abnormality has been identified on an ultrasound scan or a mammogram.
  • You may have symptoms from either breast, but no lump. If either ultrasound or mammograms show an abnormality, then a sample of tissue from this area may be required.
  • You may have no symptoms from your breasts, but a routine breast screen mammogram shows a suspicious area that requires further testing in the laboratory.

How do I prepare for a breast core biopsy?

Generally, no preparation is needed. You should bring any recent breast imaging (mammograms and/or ultrasounds) and reports for the doctor carrying out the procedure to review before doing the biopsy.

Do not wear talcum powder or deodorant on the day of the biopsy, as these can look like calcium spots (‘chalk’) on the breast X-ray. This makes it harder for the radiologist to identify the abnormality that requires biopsy. It is better to wear a two-piece outfit, so you only need to undress from the waist up.

What happens during a breast core biopsy?

The skin of the breast is washed with antiseptic and then a very fine needle is used to give local anaesthetic to numb the breast in the area for biopsy. The local anaesthetic stings for only a few seconds when it is being given, and after this the area will be numb.

A small cut (approximately 2 mm) is made in the skin and the biopsy needle is gently inserted into the breast. Several small samples are taken. When each sample is taken there is a clicking noise, and you may have a feeling of pressure in the breast where the sample is taken. The biopsy procedure may sometimes feel uncomfortable, but is not usually painful because of the local anaesthetic that has been given.

After the samples have been taken, the biopsy area will be pressed on firmly for a few minutes to reduce bruising and bleeding, and then covered with a dressing. The small cut heals normally and you will not require stitches. At the end of the procedure, the radiologist may need to insert a marker clip. A marker clip is a tiny metal clip that is inserted into the breast to mark the site of a biopsy. The clip is to identify the site of tissue that may require surgical removal or follow up.

Are there any after effects of a breast core biopsy?

The area that has been biopsied may feel a little tender for several days and there is usually some bruising. If the biopsy area is painful, you can take simple pain killers; for example, paracetamol. Medicines containing aspirin are not recommended, because aspirin thins the blood and can increase bruising or bleeding at the biopsy site. You should avoid vigorous physical exercise or heavy lifting for 24 hours after the procedure, as this may make the bruising worse.

The small skin cut that was made for the biopsy usually heals over in a few days and you will have a tiny scar less than 5 mm in size that will be barely visible once healed.

If you have had a marker clip inserted, the clip will remain inside the breast and it is not harmful to the body. Unless a further operation is required to remove more breast tissue, the clip can remain in the body forever and causes no harm.

How long does a breast core biopsy take?

The time taken for the procedure varies according to how the biopsy is done. For example, an ultrasound-guided core biopsy may take only 20 minutes. A mammography-guided core biopsy (also called a ‘stereotactic breast biopsy’) may take up to an hour.

What are the risks of a breast core biopsy?

You will usually have some bruising at the biopsy site and sometimes this may take several weeks to disappear.

There is a very small risk of infection. In the very unlikely event that the biopsy site becomes infected, a course of antibiotics may be required from your doctor.

Contact your doctor if you experience excessive swelling, bleeding, have fluid draining from the wound, redness or heat in the breast after the biopsy.

If the area of concern is located deep within the breast next to the chest wall, there is a slight risk that the biopsy needle could pass through the chest wall, allowing air around the lung that could collapse a lung. This complication is a very rare occurrence and is called a pneumothorax.

What are the benefits of a breast core biopsy?

If there is an area of concern in your breast, the core biopsy will be used to take samples of this area, so that a pathologist (a specialist doctor trained in diagnosing biopsies) can examine it and make a diagnosis. It is a way of gaining accurate information without needing an operation to surgically remove the tissue for testing.

Who does the breast core biopsy?

A breast core biopsy is usually carried out by an experienced specialist doctor, such as a radiologist, breast surgeon, breast physician or pathologist. If the area of concern cannot be felt as a lump, then the core biopsy is done using ultrasound or mammography to guide the biopsy needle into the correct position.

Where is a breast core biopsy done?

This will depend on the specialist doctor doing the test. Most core biopsies of the breast are carried out by a radiologist using ultrasound or mammographic guidance, and so are done in a hospital radiology department, breast clinic or private radiology facility.

When can I expect the results of my breast core biopsy?

The samples are sent to a pathologist and examined under a microscope. The pathologist provides a detailed report that is sent to the doctor who has requested your core biopsy (this could be your family doctor, a breast surgeon or a breast physician). Usually your doctor will already have made arrangements to discuss the results with you. The pathology results are usually available and sent to your doctor within a few days

Further information about breast core biopsy:

There are some circumstances where, at the end of the procedure, the doctor carrying out the biopsy may insert a marker clip into the area that has been biopsied. This is often done when the area of concern is very small (<5 mm) and the clip can help to find the area again if surgery is required.

Sometimes the biopsy process has removed the vast proportion or all of a possible cancerous abnormality. By inserting marker clips after the biopsy, this allows doctors to find the site of the cancer if they need to do further treatment.

Marker clips are also often used when several biopsies have been carried out in different areas of the breast

Useful websites about breast core biopsy:

Virtual Cancer Centre

*The author has no conflict of interest with this topic.

Page last modified on 31/8/2018.

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