A stereotactic biopsy is a minimally invasive diagnostic procedure used primarily to investigate suspicious areas in the breast that are too small to be felt during a physical examination. These abnormalities, often detected on a mammogram, include tiny clusters of calcium deposits (microcalcifications) or small, non-palpable masses. Precise imaging technology pinpoints the exact location of the target lesion within the breast tissue. This method allows for the collection of a tissue sample with high accuracy, providing the necessary material for a definitive diagnosis without requiring open surgery.
Preparing for the Stereotactic Biopsy
Preparation for this procedure begins with a review of current medications, as patients are generally instructed to stop taking blood-thinning agents, such as aspirin or NSAIDs, for up to seven days beforehand. This precaution significantly reduces the risk of excessive bleeding or bruising at the biopsy site. Since only local anesthesia is used, there are typically no restrictions on eating or drinking before the appointment.
Patients should wear comfortable, two-piece clothing to allow for easy access to the breast. Avoid applying deodorants, powders, lotions, or perfumes to the chest and underarm area on the day of the procedure, as these substances can create artifacts on the X-ray images, interfering with imaging. Upon arrival, the patient is positioned face down on a specialized table, which has an opening through which the breast is positioned and compressed. This prone positioning stabilizes the breast, ensuring the target area remains fixed and accessible to the radiologist working beneath the table.
How the Stereotactic Biopsy is Performed
The actual procedure begins once the breast is stabilized and slightly compressed, similar to a standard mammogram. The radiologist uses the specialized X-ray equipment to capture multiple images of the target area from different angles, typically 15 degrees apart. These images are fed into a computer system that uses triangulation to calculate the precise three-dimensional coordinates—the X, Y, and Z axes—of the suspicious lesion.
After the coordinates are established, the radiologist cleanses the skin and injects a local anesthetic, which will numb the breast tissue for the duration of the biopsy. Patients may feel a brief stinging or burning sensation as the numbing medication is administered, but the rest of the procedure should be pain-free, though some pressure may be felt. A small incision, usually less than a quarter of an inch, is then made in the skin to allow for the insertion of a specialized biopsy probe.
The probe is often a vacuum-assisted device (VAD), which is advanced to the calculated coordinates. The VAD uses suction to draw tissue into a hollow chamber and then excises a sample, allowing for the collection of multiple tissue cylinders through a single, small skin opening. The radiologist typically collects between three and twelve samples to ensure adequate tissue is obtained for analysis. A final set of X-ray images is taken to confirm successful sampling, often by verifying that microcalcifications are present within the removed tissue.
Immediate Care and Recovery After the Biopsy
Once the tissue samples are collected and the probe is removed, a tiny, inert metallic clip is deployed through the same small incision to mark the exact site of the biopsy. This marker is placed for future reference, allowing physicians to locate the area should further monitoring or surgical intervention become necessary. The marker is safe, non-magnetic, and will not be felt by the patient.
The radiologist or technologist then applies firm pressure to the biopsy site for several minutes to minimize bleeding and prevent the formation of a hematoma. After the bleeding is controlled, the small skin incision is covered with an adhesive strip, often called a Steri-Strip, and a protective bandage. A gentle post-procedure mammogram is performed to document the precise location of the newly placed marker clip.
Patients are able to leave shortly after the procedure but must adhere to specific care instructions. It is recommended to apply an ice pack intermittently to the breast for the first few hours to reduce swelling and bruising. Patients are advised to avoid strenuous activities, heavy lifting, or vigorous exercise for 24 to 48 hours. Bruising and mild soreness are normal and typically subside within a week.
Receiving and Interpreting the Results
The collected tissue samples are immediately sent to a pathology laboratory, where a specialized doctor examines them under a microscope. This analysis determines the specific nature of the cells present in the tissue. The timeline for receiving the pathology report is typically between three and seven business days, though this can vary based on the complexity of the case or the need for additional specialized testing.
The biopsy result is generally categorized into three main groups:
Benign Results
A benign result indicates the abnormality is non-cancerous and may require only routine follow-up imaging.
Atypical or High-Risk Findings
An atypical or high-risk finding suggests the presence of abnormal cells that are not yet cancer but may increase future risk, often leading to a recommendation for close monitoring or further surgical removal.
Malignant Results
A malignant result confirms the presence of cancer, requiring a prompt follow-up appointment with the referring physician to discuss treatment planning.
Regardless of the outcome, the results provide the necessary information to determine the appropriate next steps for patient care.