A stereotactic biopsy is a type of biopsy that can help to diagnose cancerous cells in breast tissue. Using a mammography machine, a radiologist uses two images of the breast tissue to take a sample of tissue for testing.
The best way to treat cancer is to catch it at the earliest stage possible. At this stage, treatment is most effective.
Various screening methods can show lumps or changes that may be cancerous tissue. If these tests are positive, the next step is often a biopsy.
In a biopsy, a radiologist removes a tissue sample for examination under a microscope to see if cancer has developed.
Nowadays, health care professionals mostly use imaging technology to guide the biopsy procedure. Often, they use ultrasound, but another option is a stereotactic breast biopsy.
This procedure uses mammogram technology to guide the needle as it takes cells for examination.
A stereotactic breast biopsy is a specific kind of biopsy.
Radiologists use specialized mammography machines to help them pinpoint any suspicious areas. These machines provide X-rays from two different angles.
The two sets of images guide the radiologist to the area of concern as they remove tissue samples. A pathologist will then analyze the samples to see if cancer is present.
A doctor may recommend this kind of biopsy if a mammogram or other examination finds:
- small deposits of calcium that could be signs of cancer
- abnormal changes in breast tissues
- a suspicious lump
- changes in an area where surgery has taken place
- irregularities in breast structure
If tests show an unusual mass, or a routine mammogram detects changes in breast tissue, it is important to find out if they are signs of cancer.
A stereotactic breast biopsy can help physicians to analyze tissue samples to understand the health of the breast better.
Before having a stereotactic breast biopsy, a person should tell the doctor:
- if they may be pregnant
- about any supplements and medications they use
Many people take blood thinners or small doses of aspirin on a doctor’s recommendation. In most cases, they will need to stop using these medications several days before the procedure.
Here are some tips on the day:
- Wear comfortable clothing, although the hospital may provide a gown for the procedure.
- Do not use deodorant, talcum powder, perfume, or body lotion around the armpits or breast.
- Leave any jewelry at home.
- Before the test, remove any dental appliances, glasses, and anything else made of metal that could interfere with the X-rays.
Mammography equipment uses X-rays to examine the breast. The design will ensure that X-rays only reach the part that is being examined.
The machine can hold, compress, and move the breast into different positions. This allows radiologists to take images of the breast from different angles.
Stereotactic breast biopsies use a special kind of mammogram machine, but it is similar to the one used in routine mammograms.
The machine helps radiologists or doctors to make sure they get the needle in the right place before taking samples.
The radiologist will use one of two different kinds of needle to collect samples of breast tissue:
- a vacuum-assisted device (VAD) can suck out several cell samples with only one insertion
- a core needle (CN), which is large and hollow, collects one sample of breast tissue per insertion
According to an article published in 2013 in Radiology, most procedures now use the VAD needle.
During the biopsy
Most stereotactic breast biopsies are done on an outpatient basis. Individuals remain awake throughout the procedure, which can take 30–60 minutes.
People generally report little or no pain during the biopsy and no scarring of the breast after. It is a good idea to ask friends or relatives for transportation to and from the appointment.
Steps of the procedure
During the procedure, the person will either:
- sit upright in a chair in front of the mammography machine
- lie face down on a moveable examination table, known as a prone table, which has an opening for the breast to fit through
The radiologist raises the table and performs the procedure from below.
Some find it uncomfortable to lie down and turn the head to one side. Cushions can help reduce this discomfort.
- The radiologist numbs the breast with a local anesthetic. There may be a slight prick.
- Next, they make a small cut in the surface of the skin where the biopsy needle will go.
- The radiologist then steers a needle through the incision and directs it to the area of concern, while two images of the affected area and computer-generated coordinates guide the process.
- When the needle is in place, the radiologist obtains more mammogram images, to make sure the needle is in position to get a good sample.
There may be clicking or buzzing sounds while the radiologist collects breast tissue samples.
- If the needle is a VAD, the radiologist will extract 8-12 samples into a collecting chamber.
- If they use a core needle, part of the needle moves forward, cutting the breast tissue as it goes and storing it in the needle. This will happen three to six times.
After collecting all the samples, the radiologist will remove the needle. They may place a marker where the biopsy was done for future reference. This will not affect the shape or appearance of the breast.
Then they take some final mammogram images.
After the procedure
This kind of biopsy does not need stitches. The radiologist will dress the incision area using steri-strips and may apply pressure for up to 5 minutes to stop or prevent bleeding.
After the procedure, the person may experience:
Ice and over-the-counter pain relievers can help.
The person should contact their doctor if they notice:
- draining of fluid
- severe swelling and bleeding
These may be the sign of an infection that needs treatment.
People should avoid strenuous activity for at least 24 hours, but they can resume normal activities after that.
A specially trained doctor, called a pathologist, will examine the breast tissue that the biopsy provides. They will determine whether or not cancerous or pre-cancerous cells are present.
They will inform the doctor who ordered the biopsy, and the doctor will share the diagnosis with the patient. Then they can discuss the next steps.
What do the results mean?
Doctors can gain a lot of information by examining the tissue samples from a biopsy.
If the biopsy finds breast cancer cells, it will also show:
- what kind of cancer it is
- if it is hormone receptor-positive
This information can help doctors and patients to develop treatment plans that will address individual needs.
If the breast tissue is normal, or it shows that an existing lump is not cancerous, the person may still need more tests to confirm that cancer is not present or to help the doctor to monitor the breast tissue over time.
A review of the effectiveness of stereotactic breast biopsies published in 2011 notes that it is highly accurate and sensitive.
This makes it very useful for determining whether or not a suspicious area in the breast is cancerous.
A stereotactic breast biopsy, like all medical procedures, will involve some risks.
- It is not suitable during pregnancy as radiation can be harmful to an unborn baby.
- It may be difficult to carry out if the person has small breasts.
- There may be some pain, although over-the-counter pain relief medication usually helps.
- In a small number of people — fewer than 1 percent — a collection of blood, known as a hematoma, can develop where the biopsy was done.
- There is a 1 in 1,000 chance of developing an infection due to the incision.
- In rare cases, the biopsy needle can go through the chest wall and cause complications.
It is not very effective in cases near the chest wall, where there are widely distributed calcium deposits, or with well-defined masses.
If a mammogram or physical examination shows an unusual lump in the breast, a doctor may recommend a biopsy.
In the past, surgery was the only option. Now, a doctor will only recommend surgery if they know that tissue also needs removing.
The stereotactic breast biopsy uses mammography equipment to guide the needle as it takes a tissue sample. It is considered an effective procedure.
The outlook for early-stage breast cancer is good.
According to the American Cancer Society, Nearly 100 percent of people who have stage 0 or stage 1 breast cancer will live for at least another 5 years. Screening and — if the doctor recommends it — a biopsy, can help protect people from developing later-stage breast cancer.
If I have a biopsy, will it make the cancer cells spread?
It is extremely unlikely that a biopsy will cause cancer cells to spread.Yamini Ranchod, PhD, MS Answers represent the opinions of our medical experts. All content is strictly informational and should not be considered medical advice.