Vacuum-Assisted Biopsy (VAB)
Vacuum-Assisted Biopsy (VAB) is a minimally invasive procedure used to obtain tissue samples from a suspicious area in the breast (or other tissues) for further examination. It is typically performed when a mammogram, ultrasound, or MRI detects an abnormality that requires further investigation to determine whether it is benign or malignant. The vacuum-assisted biopsy technique allows for the removal of larger and more contiguous samples of tissue compared to traditional needle biopsy methods.
The advantage of VAB is that it is image guided biopsy and the same imaging in which the abnormality is detected can be used to implement VAB. This is important as some of the breast lesions may not be visible on all imaging modalities. Ultrasound, mammogram and MRI are the common methods of imaging used to identify lesions in the breast.
Key Features of Vacuum-Assisted Biopsy:
1. Vacuum Suction:
- A special biopsy probe is inserted into the suspicious area under imaging guidance (ultrasound). The probe has a vacuum system that gently suctions tissue into the probe.
- The tissue is cut and collected through the probe into a collection chamber, allowing for multiple samples to be taken through a single insertion.
2. Larger Tissue Samples:
- Compared to core needle biopsy, vacuum-assisted biopsy allows for the removal of larger, more continuous samples, increasing the accuracy of the diagnosis.
- Because larger tissue samples are obtained, fewer samples are usually required to make a definitive diagnosis.
3. Single-Incision Procedure:
- VAB is usually performed through a single, small incision, making it less invasive than a traditional surgical biopsy. The incision is typically so small that stitches are not needed, and the procedure leaves minimal scarring.
4. Guidance by Imaging:
The biopsy is performed with real-time guidance from imaging techniques, such as:
- Ultrasound-Guided: Used if the abnormality is visible on an ultrasound.
- Stereotactic-Guided: Used for abnormalities detected by mammogram but not palpable, providing a 3D location of the lesion.
- MRI-Guided: Used when the abnormality is only visible on MRI, often for high-risk patients or dense breast tissue.
Procedure Steps:
1. Preparation:
- The patient is positioned based on the type of imaging guidance being used (lying on the back for ultrasound or prone for stereotactic guidance). The area of concern is identified and confirmed through imaging.
2. Local Anesthesia:
- Local anesthetic is injected into the skin and deeper tissues at the biopsy site to numb the area and prevent pain during the procedure.
3. Insertion of Biopsy Probe:
- The biopsy probe is inserted through a small incision in the skin and guided to the suspicious area using the selected imaging technique.
4. Tissue Collection:
- The vacuum suction pulls tissue into the biopsy probe, where it is cut and collected. Multiple samples can be taken from different areas of the lesion with just one probe insertion.
5. Sample Collection and Analysis:
- Once the biopsy is complete, the tissue samples are sent to a pathology lab for analysis, where they will be examined under a microscope to determine if the tissue is cancerous or benign.
6. Post-Biopsy Care:
- After the procedure, pressure is applied to the biopsy site to stop any bleeding, and a bandage is placed over the small incision. The patient may experience minor bruising or swelling, but recovery is typically quick, with minimal discomfort.
Benefits of Vacuum-Assisted Biopsy:
1. Minimally Invasive:
- The procedure is less invasive than a surgical biopsy and requires only a small incision. This means less trauma to the breast and a faster recovery time.
2. Fewer Tissue Samples Needed:
- Because VAB collects larger tissue samples, fewer samples are needed to make a definitive diagnosis, which can reduce the likelihood of needing additional biopsies.
3. High Accuracy:
- The larger and more continuous tissue samples obtained with VAB improve diagnostic accuracy, particularly for small or complex lesions.
4. Quick Procedure:
- The entire procedure typically takes about 30 to 60 minutes, and patients can often return to normal activities within a day or two.
5. No Need for General Anesthesia:
- The biopsy is performed under local anesthesia, so there is no need for general anesthesia or an extended recovery period.
Indications for Vacuum-Assisted Biopsy:
- Suspicious Mass: A lump or mass that appears abnormal on imaging but cannot be definitively identified without tissue sampling.
- Microcalcifications: Small calcium deposits that may indicate early-stage breast cancer or precancerous changes.
- Asymmetry or Architectural Distortion: An area that appears unusual or distorted on imaging.
- Breast Lesions Identified by MRI: Abnormal findings that are only visible on MRI, particularly in dense breast tissue or high-risk patients.
Risks and Complications:
Although vacuum-assisted biopsy is a generally safe and well-tolerated procedure, there are some risks associated with it, including:
- Bleeding or Bruising: Mild bleeding or bruising at the biopsy site is common but usually resolves quickly.
- Infection: Although rare, there is a small risk of infection at the biopsy site.
- Discomfort: Some patients may experience soreness, swelling, or discomfort for a few days after the procedure.
- Hematoma: In rare cases, a hematoma (collection of blood) may form at the biopsy site.
Recovery After Vacuum-Assisted Biopsy:
- Most patients can resume normal activities shortly after the procedure, although they may be advised to avoid strenuous activities for 24 to 48 hours.
- Over-the-counter pain medications like paracetomol or ibuprofen can help manage any discomfort.
- The biopsy site may remain bruised or tender for a few days, but complications are uncommon.
Conclusion:
Vacuum-assisted biopsy is a highly effective and minimally invasive option for diagnosing suspicious breast lesions. It offers greater accuracy with fewer samples and minimal discomfort compared to other biopsy techniques, and it plays an important role in the early detection and treatment of breast cancer.
