Minimally Invasive Biopsies of the Breast Offered at Mercy

Most abnormalities in the breast can be visualized on either an ultrasound or a mammogram. When there is an abnormality detected on one of these tests, your doctor may perform a biopsy to determine whether or not the abnormality is a breast cancer. The radiologists and breast surgeons at Mercy in Baltimore work together to provide women with the most appropriate methods to evaluate and diagnose breast abnormalities.

What is a Minimally Invasive Breast Biopsy?

If a significant abnormality is found on breast imaging or on clinical breast examination, a breast biopsy is often recommended. A biopsy involves the removal of a small sample of breast tissue which is then sent for examination by a pathologist to determine whether or not the abnormality is cancer.

Imaging methods such as breast ultrasound, mammography and breast MRI can be used to help guide a biopsy device through the skin to the abnormal area so that breast tissue can be obtained for analysis. The device used to obtain the biopsy can either be a large hollow needle called a core biopsy needle or a special device with vacuum attachment.

What types of Minimally Invasive Breast Biopsies are available at Mercy?

The radiologists and breast surgeons at Mercy offer several different biopsies that can be performed for further testing:

• Ultrasound-guided core biopsy (typically performed when an abnormality is visible on ultrasound)
• Stereotactic biopsy with 3D capability (typically performed when an abnormality is visible on a mammogram or 3D mammogram)
• MRI-guided biopsy (typically performed in the rare case that an abnormality is visible only on MRI) 

What is an Ultrasound-guided Core Biopsy?

An ultrasound-guided core biopsy is a minimally invasive biopsy in which the patient lies on her back on the ultrasound exam table. Ultrasound is used to locate the area of abnormality in the breast. The skin is cleansed with an antiseptic solution. Local anesthetic is injected into the skin and breast tissue to numb the area. Sometimes a very small incision is made at the skin surface.

The biopsy device is then inserted into the breast by the radiologist, using ultrasound to guide it to the targeted area. Small samples of tissue are removed and usually several passes are made through the area to obtain sufficient tissue for the pathologist to make an accurate diagnosis. After tissue is removed, the radiologist places a tiny sterile biopsy clip marker into the breast at the site of the biopsy/abnormality. This is required to document the area where samples were taken and may be used to guide a surgeon to this region if the pathology results are abnormal and surgical removal of the area is required.

The biopsy needle is then removed from the breast and pressure is held for several minutes to avoid bleeding. No stitches are required and typically a steri-strip or Band-aid is placed on the skin. A post-procedure mammogram is performed to document the position of the biopsy clip marker and to assess any post-biopsy complications. This mammogram is performed with only mild breast compression.

What is a Stereotactic Biopsy with 3D Capability?

A Stereotactic Biopsy is performed for abnormalities seen only on mammography such as areas of calcification, small masses and areas of distortion. For lesions only identified using 3D mammography (tomosynthesis), Mercy radiologists can perform a biopsy with 3D guidance.

For this procedure, the patient is positioned in a special procedure chair facing the mammography machine. The procedure is performed by the radiologist assisted by a mammography technologist. Mammography is used to visualize the abnormality and a computerized biopsy system is used to calculate the exact location of the abnormality and to assist in positioning the biopsy device. The skin is cleansed with antiseptic solution and local anesthetic is injected into the skin and breast tissue. The biopsy device is then inserted into the breast by the radiologist to obtain multiple tissue samples.

The tissue samples are X-rayed to ensure that the abnormal area was sampled. Then, the radiologist inserts a tiny sterile biopsy clip marker into the breast at the site of the biopsy/ abnormality. This is used to document the biopsy area and may be used to guide a surgeon to the same site if surgery is required. A mammogram (with mild compression) is then performed to document the position of the biopsy clip.

What is an MRI-guided Breast Biopsy?

An MRI-guided breast biopsy is rarely used, however, occasionally an MRI exam will demonstrate a suspicious breast abnormality which is not visible on mammography or ultrasound. In this case an MRI-guided biopsy is performed to make a diagnosis.

For this procedure the patient lies face-down on the MR (magnetic resonance) exam table with her breasts suspended below the table in a “breast coil,” which helps to hold the breast still. Preliminary MR imaging is performed after the patient receives an IV injection of a contrast agent and the radiologist reviews the images to locate and target the area of concern.

A computer system calculates the exact location of the abnormality in three-dimensional space. The skin is cleansed with an antiseptic solution and local anesthetic is injected into the skin and breast tissue. A biopsy probe introducer is placed by the radiologist into the breast and directed toward the abnormality. MR images are obtained to document that the probe is in good position.

A Mammotome biopsy device is then inserted through the introducer and multiple tissue samples are obtained with a single pass of the Mammotome. Once the tissue is removed, the radiologist then places a tiny metallic sterile biopsy clip marker through the introducer into the breast. This is required to document the area where samples were taken and may be used to guide a surgeon to this region if the pathology results are abnormal and surgical removal of the area is required.

MR images are then repeated to assess that the clip is in good position at the biopsy site. The biopsy introducer probe is then removed and pressure is held for several minutes to avoid bleeding. No stitches are required - typically a steri-strip is placed on the skin. A post-procedure mammogram is also performed to document the position of the biopsy clip marker and to assess for any post-biopsy complications. This mammogram is performed with only mild breast compression.

How soon will I get the results of my biopsy?

After an image-guided biopsy has been performed, the tissue is submitted to the pathology specialists at Mercy Medical Center. The pathology results are typically available after 2-3 working days and are sent to the radiologist and your referring physician.

Your radiologist will contact you to discuss your results and to give you follow-up recommendations which might include follow-up imaging or surgical consultation, depending on the diagnosis. The radiologist performing the procedure will determine if the diagnosis obtained from pathology provides an acceptable explanation for the abnormality visible on the imaging studies. If it does not, additional evaluation may be necessary such as repeat needle biopsy or surgical consultation.

If you do not receive results from your biopsy within three days, please call 410-332-9725 to speak with your radiologist.