WHAT IS VACUUM-ASSISTED BIOPSY?
The relatively new vacuum-assisted breast biopsy is a percutaneous (“through the skin”) procedure that relies on stereotactic mammography or ultrasound imaging. Stereotactic mammography uses computers to pinpoint the exact location of a breast mass based on mammograms (x-rays) taken from two different angles. The computer coordinates will help the physician to guide the needle to the correct area in the breast. With ultrasound, the radiologist or surgeon will watch the needle on the ultrasound monitor to help guide it to the area of concern. The patient will either by positioned in the upright or prone (face down) position for a vacuum-assisted biopsy.
Vacuum-assisted biopsy is a minimally invasive procedure that allows for the removal of multiple tissue samples. However, unlike core-needle biopsy, which involves several separate needle insertions to acquire multiple samples, the special biopsy probe used during vacuum-assisted biopsy is inserted only once into the breast through a small skin nick made in the skin of the patient’s breast.
First, the skin of the breast is cleaned. Then, a small amount of local anesthetic (lidocaine), similar to what one might have at a dentist’s office, is injected into the skin and deeper tissues of the breast using a small hypodermic needle. Under stereotactic or ultrasound guidance, the radiologist or breast surgeon positions the special breast probe into the area of the breast where the lesion (abnormality) is located.
After the probe has been properly positioned, a vacuum line draws the breast tissue through the aperture of the probe into the sampling chamber of the device. Once the tissue is in the sampling chamber, the rotating cutting device is advanced and a tissue sample is captured. The tissue sample is then carried through the probe to the tissue collection area (a standard pathology tissue cassette).
After a tissue sample is captured, the radiologist or surgeon then rotates the thumbwheel of the probe, moving the sampling chamber approximately 30 degrees to new position. The entire cycle is repeated, until all desired areas have been sampled (typically, eight to 10 samples of breast tissue are taken 360 degrees around the lesion).
When a sufficient number of tissue samples have been collected, the radiologist or surgeon will remove the probe and apply pressure to the biopsy site. An adhesive bandage will be applied to the skin nick. In some cases, a small sterile clip will be placed into the biopsy site of the breast to mark the location in case a future biopsy is needed. This microclip is left inside the breast and causes no pain, disfigurement, or harm to the patient. After the biopsy is complete, the tissue samples will be sent to the pathology laboratory for diagnosis.
To prepare for a vacuum-assisted biopsy, patients may eat a light meal prior to the exam and biopsy procedure. A comfortable two-piece garment should be worn. Women should not wear talcum powder, deodorant, lotion, or perfume under their arms or on their breasts on the day of the procedure (since these may cause image artifacts or other problems). Patients who take blood thinners or aspirin should talk to their physicians about whether they should discontinue using them prior to vacuum-assisted biopsy. Any jewelry worn (especially earrings or necklaces) should be easily and quickly removable.
An adhesive bandage is applied to the biopsy site after the procedure is complete. A cold pack may also be used to relieve swelling and reduce bruising. Patients may be instructed to take Tylenol or other pain relievers for discomfort if needed. Some bruising of the breast may occur during the first five to seven days after the biopsy (or longer if the initial bleeding during the biopsy was greater than usual). Temporary bruising of the breast after biopsy is normal and is usually not a medical concern.
Patients should contact their physicians if they experience any excessive swelling, bleeding, drainage, redness, or heat in the area of the biopsy or breast. Patients should also discuss the final results of the biopsy procedure with their referring physician within a few days of the procedure.
Vacuum-assisted breast biopsy is becoming more common but requires a highly skilled radiologist or surgeon who is experienced in performing the procedure. Some patients are not good candidates for vacuum-assisted biopsy or may have lesions (breast abnormalities) that are difficult to locate with minimally-invasive equipment.
However, many breast lesions (abnormalities) are able to be biopsied using the vacuum-assisted method, and if a patient is a candidate for vacuum-assisted biopsy, there are several advantages over the traditional open surgical biopsy: