Stereotactic (Stereotaxic) Breast Biopsy
The majority of females identify breast masses either themselves or after a mammogram. Mammograms are an essential part of this screening process in women over the age of 50. However, neither the mammogram nor a physical exam can tell if a breast mass is malignant. Often no masses are palpated on a physical exam.
A breast biopsy is the only way to confirm the suspicion of a cancer. Breast biopsies are normally done by the surgeon. The surgery involved anesthesia and a skin incision. Today, radiological modalities are available which can make obtaining a biopsy simpler and easier. The lesion in the breast is identified by special x rays using a computer and then a needle is placed into the abnormal area and tissues obtained for biopsy. The tissue is then processed by a pathologist. The exact positioning of the needle under X ray and aspirating the breast tissue is now a widely used technique. This technique is called Sterotactic breast biopsy.
What are the principles of a Stereotactic Breast Biopsy?
A Stereotactic breast biopsy is a radiological technique to obtain a biopsy of a breast mass. This breast mass is generally not palpable and only seen on a mammogram. The abnormal piece of breast tissue may have a ring or cluster of small number of calcium particles surrounding it. (Micro calcifications in a breast are always suspicious of cancer and represent the very early beginnings of a cancer. In all cases, the breast appears normal on physical exam. There are a number of ways to obtain biopsy of this breast tissue. The radiologist may place a needle attached to a vacuum device and obtain the material. This is less invasive than surgery. Sometimes, the radiologist places a special hooked needle with the use of X rays in to the abnormal area and allows the surgeon to remove the mass and the needle in the operating room.
What is current status of this procedure?
Stereotactic breast biopsy has been developed as an alternative to wire localized biopsy for non palpable mammographic abnormalities. Presently, about 20% of breast biopsies are performed stereotactically. This is likely to increase to 75% of all mammographically discovered lesions within the next three years. The procedure has become popular because it is very accurate and it minimizes the surgical procedure.
When is Sterotaxic biopsy indicated?
- A woman with a mammogram with a suspicious solid mass that cannot be felt on breast examination.
- A woman with a mammogram showing a suspicious cluster of small calcium deposits.
- When the breast anatomy is distorted (previous surgery).
- A new mass or area of calcium deposits is present at a previous surgery site.
- When a non surgical method is preferred by the patient.
How should I prepare for the procedure?
One should stop taking aspirin for about 4-7 days before the procedure. If you are on a blood thinner, the physician should be informed and other advice will be given. Even though this is a minor procedure, it is best to come to the radiology suite with a family member or friend. One should not eat for at least 3-5 hrs before the procedure. Wear loose clothing but a hospital gown can be provided. One should not forget to bring the old mammograms.
What does the equipment look like?
Upon arrival at the suite, you will be asked to lie down flat on your stomach; pads will be placed on your sides. The breast will be allowed to droop down into a hole in the table. The procedure can also be done in an upright chair in those who aren't able to lie down. The breast will then be cleaned and draped. A local anesthetic will be injected around the skin. The breast is then stabilized with a pair of paddle shaped instruments.
How is the procedure performed?
Once you are comfortably lying on your stomach, the breast area is cleansed with an antibiotic solution and sterile drapes are placed around you. A local anesthetic is injected to numb the area. A small cut is made in the skin to allow for the hollow needle to enter.
The breast is then placed in compression. Images are then obtained using digital x-rays. The main objective of the x rays is to make sure that the needle is accurately placed in the breast lesion. This is aided by the computer which localized the coordinates for positioning of the needle.
Prior to the biopsy, the mass position is again confirmed with some cross sectional imaging. The needle is placed into the mass area under x ray guidance and the needle tip placement is confirmed. Numerous Samples from the breast area are obtained. The images of the breast are repeated to ensure that the samples have been obtained from the correct place and a small clip is left in the area- for future reference from where the samples were obtained. The needle is removed and a small dressing is placed. After the procedure, one may go home.
What will I experience during the procedure?
The procedure takes anywhere from 45-120 minutes. There is mild pain which is controlled with a local anesthetic. There are no skin incisions except for a needle puncture hole. The majority of women complain of the discomfort they feel lying on their stomach during the time period of the test.
The recovery is fast. There may be mild bruising around the breast for the next few days which will resolve fast. The mild pain is easily controlled with an over the counter pain mediation.
One is asked not to resume any exercise or physical activity for the first 24 hours. The breast area should be kept clean and dry for a couple of days. An ice pack may help decrease the pain and limit the swelling.
Who interprets the results and how do I get them?
Once the tissue samples are obtained, the tissue is sent to the pathologist. The final results take at least 2-3 days. The results will be sent to your physician who will let you know the results. If here is any evidence of a malignancy, you will be referred to the appropriate consultant for further therapy.
What are the advantages vs. disadvantages?
- Patients have minimal discomfort during or after the procedure.
- The technique allows for biopsy of lesions that are not visible on ultrasound.
- The technique allows for biopsy of lesions that are not even palpable on a physical exam.
- Patients can usually resume normal activities by the following day.
- Stereotactic biopsies have been shown to be very accurate.
- They are as accurate as an open surgical biopsy.
- Benefits of the procedure include less patient discomfort, quicker recovery, decreased scarring, and decreased cost.
- Traditional mammographic directed biopsies require that the lesion be seen on two views, but with stereotactic techniques abnormalities that are seen on one view can be removed.
- The procedure is much cheaper than the conventional open surgery.
- Unlike open surgery, the breast structure and anatomy is preserved.
- Recovery after the procedure is much faster than the open procedure.
- In some cases, the entire lesions can be removed with a vacuum assist device.
- The procedure can be associated with bleeding and control can be difficult because of the small hole made by a needle. The risk of bleeding is small.
- rarely, the lesions can be missed and a second procedure may be required.
- There is more radiation exposure compared to open technique.
- Pregnant females should not undergo the procedure because of the risk of radiation exposure to the fetus.
What are the limitations of a Stereotactic Breast Biopsy?
Breast lesions that have diffuse calcium deposits over the entire breast are not good candidates for the procedure.
Rarely, even after a successful biopsy, the tissue diagnosis remains uncertain and a surgical biopsy will be necessary, especially when atypical or precancerous cells are found on core biopsy.
Vague lesions on a mammogram are best biopsied with open surgery.
Technical problems make it difficult in to obtain biopsies in patients with small breasts or in lesions that are up against the chest wall.
Who decides whether to have an open or Stereotactic biopsy?
The decision as to whether a lesion can be removed stereotactically is usually made by the surgeon and the radiologist.
By ScanDirectory.com Staff
Updated: July 19, 2007