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.
Two companies currently manufacturer
vacuum-assisted breast biopsy systems, and often, vacuum-assisted biopsy will be referred
to by the brand name: either Mammotome
made by Johnson & Johnson Ethicon Endo-Surgery or MIBB (which stands for Minimally Invasive Breast Biopsy) made by
Tyco/United States Surgical Corporation. In 1999, a hand-held version of the Mammotome was
also approved by the U.S. Food and Drug Administration (FDA).
How is Vacuum-Assisted Biopsy
Performed?
First, the skin of the breast is
cleaned. Then, a small amount of local anesthetic (lidocaine), similar to what one might
have at a dentists 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.
How Should Patients Prepare for
Vacuum-Assisted Biopsy?
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.
What Should Patients Expect
After Vacuum-Assisted Biopsy?
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.
What are the Advantages and
Disadvantages to Vacuum-Assisted Biopsy?
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:
| Vacuum-Assisted Biopsy |
Open Surgical Biopsy |
| Minimally
invasive, requires 0.25 inch incision (approximately 0.6 cm) |
Requires
1.5 to 2 inch incision (approximately 3.8 cm to 5.1 cm) |
| Usually
no significant scarring |
May
potentially cause substantial scarring |
| Performed
under local anesthesia |
Performed
under local or general anesthesia |
| Does
not require stitches |
Requires
stitches |
| Procedure
takes less than one hour |
Procedure
takes longer than one hour |
| Patients
can usually return to normal activity shortly after procedure |
Requires
at least one full day of recovery after the procedure |
| Typically
costs significantly less than open surgical biopsy |
Typically
costs more than vacuum-assisted biopsy and is usually the most expensive method of biopsy |
| Usually
provides a definitive diagnosis based on tissue samples |
Provides
a definitive diagnosis based on tissue samples |
Updated: August 29, 2007
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