Percutaneous imaging-guided biopsy is an increasingly used method for diagnosing breast abnormalities, particularly those that are nonpalpable. Imaging guidance can be provided with either radiographic (usually stereotactic) imaging or sonographic imaging. In the near future, the technology to provide guidance under magnetic resonance imaging (MRI) will likely also become available.
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.
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. 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.
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 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
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 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
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. 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. 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. 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 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.