Stereotactic-Guided Vacuum-Assisted Core Biopsy

A breast lump or an abnormality in the breast is often detected by physical examination, mammography or other imaging studies. However, it is not always possible to tell from these imaging tests whether a growth is benign or cancerous.

To determine this, a breast biopsy is performed to remove some cells—surgically or through a less invasive procedure involving a hollow needle—from a suspicious area in the breast and examine them under a microscope. Image-guided needle biopsy is not designed to remove the entire abnormality, just a small portion for testing.

An image-guided biopsy is performed when the abnormal area in the breast is too small to be felt, making it difficult to locate by hand. In an MRI-assisted breast biopsy, a high-powered magnet is used to help guide the radiologist’s instruments to the site of the abnormal growth.

What Are Some Common Uses of the Procedure?
A stereotactic breast biopsy is performed when a mammogram shows a breast abnormality such as:

  • A suspicious solid mass
  • Microcalcifications (a tiny cluster of small calcium deposits)
  • A distortion in the structure of the breast tissue
  • An area of abnormal tissue change
  • A new mass or area of calcium deposits present at a previous surgery site

Stereotactic breast biopsy is also performed when the patient or physician strongly prefers a non-surgical method of assessing a breast abnormality. Stereotactic guidance is used in two biopsy procedures:

  • Core needle (CN), which uses a large hollow needle to remove one sample of breast tissue per insertion.
  • Vacuum-assisted device (VAD), which uses a vacuum-powered instrument to collect multiple tissue samples during one needle insertion.

How Should I Prepare?
You may be asked to remove some or all of your clothes and wear a gown during the exam. You may also be asked to remove jewelry, dentures, eyeglasses and any metal objects or clothing that might interfere with the X-ray images.

Women should always inform their physicians if there is any possibility that they are pregnant. Some procedures using image guidance are typically not performed during pregnancy because radiation can be harmful to the fetus. You should not wear deodorant, powder, lotion or perfume under your arms or on your breasts on the day of the exam.

Prior to a needle biopsy, you should report to your doctor all medications that you are taking, including herbal supplements, and if you have any allergies, especially to anesthesia. Your physician will advise you to stop taking aspirin or blood thinners three days before your procedure.

Also, inform your doctor about recent illnesses or other medical conditions.

You may want to have a relative or friend accompany you and drive you home afterward. This is recommended if you will have to be sedated.

How Is the Procedure Performed?
A specially trained radiologist most often will perform your stereotactic breast biopsy. You will lie face down on a moveable exam table and the affected breast or breasts will be positioned into openings in the table. The table will then be raised and the procedure performed beneath it. The breast will be compressed and held in position throughout the procedure. A local anesthetic will be injected into the breast to numb it.

Several stereotactic pairs of X-ray images will be taken. A very small nick will be made in the skin at the site where the biopsy needle is to be inserted. The radiologist will then insert the needle and advance it to the location of the abnormality using the X-ray and computer-generated coordinates. X-ray images are again obtained to confirm that the needle tip is actually within the lesion.

Tissue samples are then removed using one of two methods:

  • In a core needle biopsy, the automated mechanism is activated, moving the needle forward and filling the needle trough, or shallow receptacle, with “cores” of breast tissue. The outer sheath instantly moves forward to cut the tissue and keep it in the trough. This process is repeated three to six times.
  • With a vacuum-assisted device (VAD), vacuum pressure is used to pull tissue from the breast through the needle into the sampling chamber. Without withdrawing and reinserting the needle, it rotates positions and collects additional samples. Typically, eight to 10 samples of tissue are collected from around the lesion.

After the sampling, the needle will be removed and a final set of images will be taken.

A small tissue marker may be placed at the site so that it can be located in the future if necessary. Once the biopsy is complete, pressure will be applied to stop any bleeding and the opening in the skin will be covered with a dressing. No sutures are needed. A mammogram may be performed to confirm that the marker is in the proper position. This procedure is usually completed within an hour.

What Can I Expect?
Prior to the procedure, a nurse will meet with you to complete an assessment, explain the procedure and provide the appropriate paperwork. The radiologist then meets with you to answer any questions and has you sign consent forms for the procedure.

The nurse will review the discharge instructions with you before you leave. A copy of the discharge instructions will be provided for you to take home and refer to. Download our Breast Biopsy Pre- and Post-Procedure Instructions to learn more about what you can expect with this procedure. 

What Are the Benefits and Risks?
Benefits

  • It’s less invasive than surgical biopsy, leaves little or no scarring and can be performed in less than an hour at an outpatient imaging center.
  • It’s an excellent way to evaluate calcium deposits or tiny masses that are not visible on ultrasound.
  • The procedure is lower cost than open surgical biopsy.
  • Generally, the procedure is not painful and the results are as accurate as when a tissue sample is removed surgically.
  • No breast defect remains, and unlike with surgery, it does not distort the breast tissue and make it difficult to read future mammograms.
  • Recovery time is brief and patients can soon resume their usual activities.

Risks

  • Because the vacuum-assisted device removes slightly larger pieces of tissue than other types of needles, there is a risk of bleeding and forming a hematoma, or a collection of blood, at the biopsy site. The risk, however, appears to be less than 1% of patients.
  • An occasional patient experiences significant discomfort, which can be readily controlled by non-prescription pain medication.
  • Any procedure where the skin is penetrated carries a risk of infection.
  • Doing a biopsy of tissue located deep within the breast carries a slight risk that the needle will pass through the chest wall, allowing air around the lung that could collapse a lung. This is a rare occurrence.
  • Women should always inform their physician or X-ray technologist if there is any possibility that they are pregnant.

Who Interprets the Results and How Do I Get Them?
A pathologist examines the removed specimen, makes a final diagnosis and sends a signed report to your primary care or referring physician, who will discuss the results with you.

Gwinnett Medical Center Imaging has multiple convenient Atlanta-area locations in Lawrenceville, Hamilton Mill and Duluth. If you would like to schedule an appointment, please call 678-312-3444.