Stereotactic Breast Biopsy: Indications and Results

In addition to imaging options, tissue sampling can be performed with a variety of techniques, including fine-needle aspiration cytology or core-needle biopsy. If a core biopsy is performed, it can be done using either a gun-needle combination or vacuum suction-needle device.

 This paper will address various issues relevant to core-needle biopsy of the breast under stereotactic imaging guidance. Patient and equipment selection, indications, contraindications, complications, limitations, and advantages will be discussed. The role of stereotactic core biopsy in patient management will also be addressed.

Advantages of Imaging-Guided Biopsy

As compared with traditional surgical biopsy, stereotactic core biopsy of the breast offers several advantages. For the patient, the traditional surgical approach requires a presurgical visit to the surgeon, another visit for the surgical procedure to be performed, and at least one more visit for postoperative care. At least 3 days are required for these physician visits, resulting in considerable time lost from work. The personal expense resulting from these visits may, therefore, may be significant.

In addition, the volume of tissue removed during a surgical procedure can cause contour deformity of the breast. Because 70% to 80% of breast biopsies are performed for benign lesions, only the volume of tissue necessary to make the diagnosis of a benign process is needed by the pathologist. Removal of additional tissue in such cases, with its attendant cosmetic issues, is medically unnecessary. Also, surgical removal of tissue can cause scarring within the breast that can be confused with carcinoma on future mammograms. This confusion can result in additional biopsies being performed.

Beyond the inconvenience and possible cosmetic effects of surgical biopsy, the time from discovery of a breast lesion to reporting of the pathology results can be long. The impact of the emotional stress on the patient and her family during this waiting period can be considerable.

In contrast to surgical biopsy, stereotactic core biopsy and other imaging-guided needle biopsy procedures can be performed after the patient has completed her imaging work-up and has consulted with the radiologist. Therefore, scheduling issues can be minimized, and a visit with an additional physician can be eliminated. In some instances, it may be possible for a facility to perform the biopsy at the time of the imaging work-up. However, equipment and personnel availability and medical considerations will sometimes make this impossible.

Because a needle biopsy requires the removal of only a small volume of tissue, post-biopsy scarring that is mammographically visible does not develop.[1] Therefore, there is no chance of confusing the scar with a possible new carcinoma. Also, the possibility of cosmetic deformity of the breast is eliminated.

Moreover, because a stereotactic biopsy is usually completed more quickly than a surgical biopsy, results are available faster, and the patient has to cope with anxiety about the procedure for a shorter period.

Cost Reduction

Stereotactic core biopsy also significantly reduces the cost of performing a breast biopsy. Using fees obtained from either Medicare or relative values for physicians, Liberman et al[2] found that stereotactic core biopsy was less than one-half the cost of surgical biopsy. They estimated that the routine use of stereotactic core biopsy, when appropriate, could result in an annual national savings approaching $200 million.

In a study conducted at the University of Utah, Doyle et al[3] determined that the use of large-core needle biopsy could reduce the cost of biopsy per cancer detected from $11,555 to $8,356--a 28% reduction. When estimating the cost per year of life saved with mammographic screening, Lindfors and Rosenquist[4] found a comparable reduction, 23%, when core biopsy was used to replace surgical biopsy and when screening was done on women between the ages of 40 and 85 years.

In the current era of capitated care and limited health care dollars, the reduction in the cost of care that can result from the use of stereotactic core biopsy becomes increasingly important, as long as these programs are instituted without compromising the quality of patient care.

Patient Selection

Lesions Apropriate
for Stereotactic Biopsy

Stereotactic core biopsy is an appropriate technique for the biopsy of nonpalpable, mammographically evident lesions that require tissue sampling. These include lesions that, according to the American College of Radiology Breast Imaging Reporting and Data System (BI-RADS), would be classified as category 4 lesions, ie, those that are indeterminate but have a high enough possibility of malignancy to require biopsy.[5] Category 5 lesions, ie, those that have a pattern highly suggestive of malignancy, may also benefit from stereotactic core biopsy when preoperative confirmation of the diagnosis of carcinoma by tissue sampling will make it possible to downstage a two-stage surgical procedure (initial surgical biopsy followed by a second surgery for definite treatment) to a one-stage surgical procedure. In a one-stage procedure, the surgery to perform the biopsy is replaced by stereotactic core biopsy.

One study of the impact of core biopsy on the surgical management of 197 mammographically detected breast carcinomas showed that breast cancer was treated using a single surgical procedure in 84% of women whose cancers were confirmed histologically with stereotactic core biopsy vs 21% of women who did not undergo a stereotactic procedure.[6] Interestingly, at the time of the definitive surgical procedure, there was no difference in the ability of the surgeon to obtain resection margins free of tumor in either of the study groups.

In an assessment of the impact of stereotactic core biopsy on the cost of treating lesions that had a very high likelihood of being carcinomas based on their mammographic patterns (BI-RADS category 5), stereotactic core biopsy was also useful in reducing the number of surgeries required and the cost of treatment.[7] In 31 women who underwent stereotactic core biopsy for highly suspicious calcifications seen on their mammograms, the number of surgical procedures was reduced in 42% of patients, and cost savings were estimated at about $100 per patient.

Women with multiple lesions within a single breast may also benefit from stereotactic core biopsy, as multiple areas can be biopsied as part of a single biopsy procedure, if necessary. Some patients will present with an obvious, palpable cancer and an indeterminate nonpalpable mammographic abnormality; in other instances, more than one suspicious mammographic abnormality may be present. In these situations, it is possible to determine whether the patient has multiple sites of carcinoma within a breast, thereby contraindicating breast conservation, or whether she has only a single carcinoma and can be treated without mastectomy.

In a study of 25 women with multiple breast lesions, Rosenblatt et al[8] found that, in 80% of patients, stereotactic core biopsy was able to determine which surgical procedure was needed. In these cases, stereotactic biopsy either confirmed the need for mastectomy or eliminated the need for preoperative needle localization.

It is important for the physician considering stereotactic core biopsy in an individual patient to reflect on whether or not this procedure will increase or decrease the number of interventions required and will increase or decrease the cost of care for that patient. Stereotactic core biopsy should not be used when it is thought that it will add an additional interventional procedure to those required for diagnosis. However, if stereotactic core biopsy may possibly decrease the number of surgeries needed to treat a patient, it should be considered an appropriate procedure. In some instances, therefore, the radiologist performing stereotactic core biopsy will need to consult with the breast surgeon to determine how the results of stereotactic core biopsy will impact on treatment. In lesions that are most likely to be benign, this consultation may be unnecessary.