Lt Col Flemings
If a physical examination, mammogram, or other imaging test reveals a suspicious mass in the breast, your provider may order a biopsy. Major Spencer, what can you tell us about breast biopsy?
Well, Dr. Flemings, a breast biopsy is a technique used to remove the suspicious tissue so that it can be tested. A biopsy is the primary method used to confirm the presence of cancer. There are several types of biopsies, including:
- Fine needle aspirations
- Core needle biopsies
- Stereotactic biopsies, and
- Excisional biopsies
The choice of which type to use depends on several factors. These factors include:
- How suspicious the abnormality appears
- The size of the abnormality
- The location of the abnormality in the breast
- How many abnormal areas are present
- Other medical problems, and
- Your personal preferences
Your provider will discuss with you the advantages and disadvantages of different biopsy procedures, and recommend the procedure most appropriate for your condition.
Fine Needle Aspiration Biopsy (FNA)
A fine needle aspiration biopsy, or FNA, is a test that uses a thin needle to remove fluid or a small amount of tissue from a lump or abnormal area of the breast. This material is then checked for evidence of cancer. The needle can be guided into the area of the breast abnormality while the provider is feeling the lump. If the lump can’t be felt easily, the provider might use an ultrasound or another method called a stereotactic needle biopsy to guide the needle. With ultrasound, the provider can watch the needle on a screen as it moves toward and into the mass.
Once the needle is in place, fluid can be drawn from the cyst or mass, if any is present. Bloody or cloudy fluid can mean either a benign cyst or cancer. If the lump is solid, small tissue fragments can be withdrawn through the needle. Solid lumps can be the result of cancer or of several types of benign breast conditions.
The fluid or tissue drawn by the needle is sent to the lab, placed onto glass slides, and treated with stains to make them more visible under a microscope. Microscopic examination of these samples can often tell whether a breast abnormality is benign or malignant. In other cases, the results of the fine needle aspiration are not definitive, and another type of biopsy is required.
Core Needle Biopsy
During a core needle biopsy, or CNB, a needle is used to remove a small cylinder of tissue from a breast abnormality. The sample of tissue is usually about 1/16 inch in diameter and ½ inch long. The CNB is conducted with local anesthesia in the provider’s office or clinic. The CNB can sample and examine tumors felt by your provider, as well as smaller abnormalities found by ultrasound or other methods.
When performing a CNB, your provider may use a device known as a Mammotome. During a Mammotome biopsy, also called a vacuum-assisted biopsy, a surgeon inserts a tube larger than those used in a typical core needle biopsy into the breast tissue. The provider then uses suction to draw a cylinder of breast tissue into the tube, and a small rotating knife cuts and removes the tissue for examination. The needle is inserted only once and rotates to get the needed cores. The Mammotome is performed with local anesthesia.
Another tool that can be used during a core needle biopsy is called the advanced breast biopsy instrument, or ABBI. The ABBI uses a rotating circular knife to remove a larger cylinder of tissue for examination. The ABBI procedure removes more tissue than other types of biopsies and are performed using local anesthesia.
During a stereotactic biopsy, a computerized mammography machine uses intersecting coordinates to pinpoint the lump or area of tissue change. The tissue is removed and then examined under a microscope, allowing your provider to make a more accurate diagnosis.
A stereotactic breast biopsy is most useful when a mammogram shows a cluster of microcalcifications or an area of abnormal tissue change. Because these changes cannot be felt during breast examination, a stereotactic biopsy allows the provider to precisely locate the area of concern.
In some cases, your provider may suggest surgery to remove all or part of a lump for examination under a microscope. An excisional biopsy is used to remove the entire lesion, or breast abnormality, such as a lump or area containing calcifications. The surgeon will also remove a small amount of healthy surrounding tissue, known as a margin.
A surgical biopsy is usually performed in the hospital outpatient department using local anesthesia. During the biopsy, the surgeon may use a procedure called a wire localization to help locate the lump or area of interest, especially if the lump is too small to locate by touch. After numbing the area with local anesthesia, a thin hollow needle is placed into the breast and x-ray pictures are taken to guide the needle to the suspicious area. A thin wire is placed through the center of the needle. A small hook at the end of the wire keeps it in place. The hollow needle is then removed, and the surgeon uses the wire as a guide to locate the abnormal area to be removed.