To demonstrate this point, let’s conduct an experiment.  Focus your eyes on one point of this page, then alternate covering each eye one at a time.  You will notice that the image you see changes slightly.  This is because, as you cover your eye, your brain loses information from the other eye and has difficulty locating the exact point in space on which you are focusing.  In fact, your brain does a remarkable amount of compensation for this lack of information and the difference you see when covering your eye is very subtle.  Unfortunately, the computer needs all of this information.

Following location of the lesion on the X-ray images on the computer monitor, the exact point, which the surgeon wishes to biopsy, is marked with the mouse pointer on each image.  The x, y, and z, coordinates are then displayed and transmitted to the biopsy platform beneath the hole in the table where the patient is lying and the breast is fixed.  The biopsy device is then moved into position and the biopsy is performed using local anesthesia only.

The procedure described above takes about an hour in a designated procedure room and does not require the operating room or radiology.  The patient is discharged to home shortly afterward.  The resulting incision is between ¼” and 1 ½” in length depending on whether the mammotome or ABBI technique is employed.  Pain and discomfort following these procedures is minimal.

The choice of which technique is used depends largely on the size and location of the lesion within the breast, and surgeon preference.  The ABBI system requires that the lesion be less than 2.0 cm in diameter and located centrally in the breast, not too near the chest wall, and not too near the nipple.  The main advantage of this system over the mammotome or MIBB systems is that the ABBI system removes a core of tissue up to 2cm diameter, which can be examined under the microscope and the results are extremely reliable.  However, many lesions are not amenable to this technique because of size or relative location within the breast.

The mammotome and MIBB systems are both very similar in that they allow introduction of a large bore needle into the breast and using the stereotactic localizing technique described above, fragments of tissue are removed for examination.  These systems are not as stringent in terms of lesion size and location, though the same rules still apply to some extent.  However, microscopic examination of fragments of tissue is not always reliable, and on occasion it may be necessary to undergo a standard needle localization breast biopsy following a mammotome or MIBB biopsy with equivocal results. 

As suggested above, some patients may not be candidates for these procedures because of lesion size, relative location in the breast ore inability to see the lesion on the stereotactic imager that is visible on mammogram.  For this reason, prior to actually performing a stereotactic biopsy I usually obtain a pre-screening stereotactic image in which the patient is placed on the table and stereotactic images are performed.  This is generally done a few days prior to the actual procedure so that the appropriate calculations can be done and assurances given that the lesion is approachable via the stereotactic technique.  If it is found that the lesion is not amenable to stereotactic biopsy then standard needle localization breast biopsy is undertaken.

Patients generally prefer these techniques to standard needle localization because the cosmetic result is superior and there is far less surgical dissection necessary in the performance of these procedures and thus less post-operative pain.  Additionally, the patient spends much less time in the hospital for the performance of this procedure since it can be performed in a procedure room dedicated to this procedure, rather than having to have two separate procedures performed, one in X-Ray and one on the operating room, as is necessary for standard needle localization breast biopsy.  Finally, and most importantly, the specimens obtained from these biopsies are more than adequate to establish an accurate diagnosis.   Of course, if any question as to diagnosis remains following a stereotactic biopsy, then a needle localization breast biopsy may be warranted.

I hope I have effectively answered any of the most common questions the reader may have.  As always I encourage anyone interested to contact me via E-mail.