A biopsy is a procedure in which a sample of tissue is taken from the breast and then examined under a microscope by a pathologist. While various imaging procedures such as mammography can raise suspicions of cancer, only a biopsy can definitively diagnose cancer.
In the past, the most common way to biopsy a suspicious lump in the breast was to surgically remove it while the patient was under full sedation. Often, if the biopsy showed there was cancer, a mastectomy was done during the same operation. So many women went into the operating room not knowing if they had cancer and woke up having had a mastectomy.
Today, much less invasive biopsy procedures are available. Women who are found to not have cancer can avoid surgery and anesthesia, and women who do have cancer can take some time to decide on a treatment plan.
Fine Needle Aspiration Biopsy (FNA)
A fine needle aspiration biopsy is a simple procedure that can be done in a doctor's office. It is used to biopsy lumps that can be easily felt by the doctor.
The doctor inserts a very thin needle into the area of the breast where the lump is found. A tiny bit of tissue or fluid is withdrawn (or aspirated) from the lump and placed on a slide for examination under a microscope. This type of biopsy is relatively quick; any discomfort lasts only a few seconds.
If the lump turns out to be a fluid-filled cyst, the needle will withdraw the fluid and the lump will collapse.
This procedure is also called an aspiration biopsy or suction biopsy.
Core Needle Biopsy
A core needle biopsy may be used if a larger sample of tissue is needed than can be obtained with a fine needle aspiration biopsy. It may also be used if the tissue removed during a needle aspiration biopsy does not yield a definitive diagnosis.
This type of biopsy requires a local anesthetic. The doctor inserts a larger, hollow needle into the breast. A small cylinder of tissue about one inch long is removed and sent to the laboratory for analysis.
A core needle biopsy may result in more pain and bleeding than a fine needle aspiration biopsy, and may require a stitch in the skin to close the wound.
Ultrasound-Guided Biopsy
In this procedure, the doctor uses ultrasound images to guide insertion of a biopsy needle into the suspicious area. A gel is applied to the skin, and an ultrasound transducer is passed over the skin. Sound waves are emitted from the transducer and bounce off breast tissues. A computer assembles the data from the waves into an image on a screen.
The biopsy procedure itself is either a fine needle aspiration biopsy or core needle biopsy.
Stereotactic Biopsy
A stereotactic biopsy may be done when a mass or microcalcification is only visible on the mammogram. The doctor performs a standard needle biopsy, but instead of locating the lump by touch, he or she uses x-ray images from a mammogram of the breast to guide insertion of the needle.
In this procedure, you will lie face down on an examining table with your breast suspended through an opening. The table is then elevated, allowing the doctor to work from below. The breast is compressed between plates, as in a mammogram. Two or more images of the breast are taken and compiled in a computer to create a 3-dimensional picture. The doctor anesthetizes the breast, makes a tiny incision in the skin, and inserts a core needle to the area to be biopsied, using the 3-D image as a guide. Several tissue samples may be taken during the procedure.
Some medical facilities use a device called a Mammotome to perform a stereotactic biopsy. This procedure is the same as above, except that the core needle uses suction at several points along it to pull in tissue samples. The probe needs to be inserted only one time to get several samples.
A bandage will be applied to cover the incision. The entire procedure takes about an hour, and may be somewhat uncomfortable, mainly because you must remain still for much of that time.
Surgical Biopsy
A surgical biopsy may be done if other procedures did not yield enough tissue to make a diagnosis, if the doctor needs to confirm a diagnosis made after a needle aspiration biopsy, or when a mammogram clearly indicates that a lump should be removed.
A surgical biopsy takes place in an operating room, but it does not usually require an overnight stay in the hospital. The patient receives either local anesthesia and sedation or general anesthesia. The doctor uses a scalpel to make an incision in the skin and removes all or part of the suspicious tissue. If the lump is small or hard to find, before the operation begins, a radiologist will locate the area on a mammogram and insert a thin wire into the breast. The surgeon then uses the wire to locate the appropriate area. This is called a wire localization or needle localization biopsy.
In an incisional biopsy, only a sample of tissue from the lump is removed. In an excisional biopsy, the entire lump is removed. An excisional biopsy may require a larger incision than an incisional procedure. The doctor will use a few stitches to close the wound.
The tissue sample is immediately sent to a laboratory for examination by a pathologist. Preliminary results are sometimes available by the time you wake up in the recovery room. However, keep in mind that these results are only preliminary; they can change after a more thorough exam of the tissue is completed.
