Lumps or abnormalities in the breast are often detected by physical exam, mammography, or by other imaging studies. However, it is not always possible to determine from imaging tests whether a growth is benign or malignant/ cancerous. A breast biopsy is performed to remove some cells from a suspicious area through a less invasive procedure involving a hollow needle. The cells are then examined under a microscope to establish a diagnosis.
Imaging-guided biopsies are performed by advancing a special needle into a suspicious area, under direct visualization, to withdraw a small core of tissue from the abnormality. In the case of ultrasound-guided breast biopsy, ultrasound imaging is used to help guide the radiologist’s instrument into the abnormal growth.
Why Perform an Ultrasound-Guided Breast Biopsy?
Ultrasound-guided breast biopsy may be recommended if a breast ultrasound demonstrates an abnormality such as:
- A suspicious solid mass
- Distortion in the structure of the breast tissue
- An area of abnormal tissue change
- There are times your doctor may decide that ultrasound guidance is appropriate for biopsy, even for a mass that can be felt
Ultrasound guidance is used to perform the following procedures:
Fine needle aspiration (FNA), which uses a very small needle to extract fluid or cells from the abnormal area — typically for cyst aspiration.
Vacuum-assisted core biopsy, which uses a hollow needle and a vacuum powered instrument to collect tissue samples during one needle insertion — typically for biopsy of a solid mass.
How does the procedure work?
The radiologist inserts the biopsy needle through the skin and advances it into the abnormality. Continuous ultrasound imaging allows the physician to view the biopsy needle as it advances to the location of concern. Tissue samples are then removed in real-time.
The procedure is less invasive than a surgical biopsy, leaves little or no scarring, and is performed in less than 30 minutes.
Ultrasound imaging uses no ionizing radiation.
Ultrasound-guided breast biopsy reliably provides tissue samples that can show whether a breast lump is benign or malignant.
Ultrasound-guided breast biopsy is able to evaluate abnormalities that reside in difficult to reach places such as under the arm or near the chest wall. These areas are very difficult to access with stereotactic biopsy.
Ultrasound-guided biopsy is less expensive than other biopsy methods, such as open surgical biopsy or stereotactic biopsy.
Recovery time is brief and patients can soon resume their usual activities.
There is a risk of bleeding and development of a hematoma or collection of blood at the biopsy site. However, the occurrence of these risks is noted to happen in less than 1% of patients.
An occasional patient will experience significant discomfort, which can be readily controlled by non-prescription pain medication.
Any procedure that penetrates the skin carries a risk of infection. The possibility of contracting an infection requiring antibiotic treatment is extremely low (less than 0.1%).
You will be asked to wear a gown during the procedure, and you may need to remove jewelry from the area to be examined.
You should report all medications you are taking (including herbal supplements) to your doctor before a needle biopsy. Please also let your physician know if you have any allergies. You should stop taking aspirin or a blood thinner two days before your procedure.
The procedure is performed with local anesthetic (like in the dentist’s office), and not with sedation. Although it is not required, you may want to have a relative or friend accompany you and drive you home afterward.
Sterile equipment, such as syringes, needles, sponges, a scalpel and a specimen cup, will be used during the procedure.
What You Can Expect
How is the procedure performed?
Imaging-guided biopsies are considered minimally invasive procedures, and are typically performed on an outpatient basis. You will be awake during the procedure.
You will be positioned lying face up on the exam table. The skin is cleansed with antiseptic solution and then local anesthetic is injected into the breast to numb the area. While scanning the breast, the radiologist will locate the abnormality. A very small nick is made in the skin where the biopsy needle is to be inserted. While monitoring the abnormality with ultrasound, the radiologist will then insert the needle directly into the abnormality. You may feel some pressure when the biopsy needle is inserted, but you should not feel pain. When the needle is positioned, tissue samples are removed using the vacuum-assisted needle. As tissue samples are taken, you may hear a machine-like sound from the device. Without withdrawing and reinserting the needle, the radiologist will reposition or rotate the needle to collect additional samples. Typically, five to seven samples of tissue are collected. After this sampling, the needle is removed. The radiologist may introduce a tiny biopsy marker into the region that was biopsied so that it can be located in the future if necessary. If a marker is left inside the breast to mark the location of the biopsied abnormality, it will not cause pain, disfigurement or harm. It is MRI safe and will not set off a metal detector.
Once the biopsy is complete, pressure will be applied to the breast in order to stop/prevent any bleeding. The incision will then be covered with a dressing. No sutures are needed.
A mammogram may be performed to confirm that the marker is in the proper position. The procedure is usually completed within 30 minutes.
What will I experience after the procedure?
Patients who undergo biopsy are instructed to ice the biopsied area throughout the remainder of the day. This will decrease the likelihood of a hematoma or bruise. If you experience swelling and bruising following your biopsy, you may be instructed to take an over-the-counter pain reliever (Tylenol) and to continue icing the area. Temporary bruising is not unusual.
It is important to contact the physician who performed the procedure if you experience excessive swelling, bleeding, drainage, redness or heat in the breast.
Avoid strenuous activity for 24 hours after the biopsy. After that period of time, you will usually be able to resume normal activities.
Who interprets the results and how do I get them?
A pathologist examines tissue samples obtained during the biopsy and will provide the final diagnosis. The Diagnostic Imaging Specialists of Chicago radiologist will contact you and your physician with results by the end of the next business day.