Breast Biopsy

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Breast Biopsy Performed by Hill Medical

What is a Breast Biopsy?

A breast biopsy is performed to remove some cells—either surgically or through a less invasive procedure involving a hollow needle—from a suspicious area in the breast and examine them under a microscope to determine a diagnosis. Image-guided needle biopsy is not designed to remove the entire lesion, but most of a very small lesion may be removed in the process of biopsy. Image-guided biopsy is performed when the abnormal area in the breast is too small to be felt, making it difficult to locate the lesion by hand. There are times when your doctor may decide that image-guidance for biopsy is appropriate even for a mass that can be felt.

A breast biopsy is a minimally invasive outpatient procedure which allows you to return to your normal activities within a few hours after the completion of the procedure. A breast biopsy is often recommended by a radiologist if any abnormalities are detected on your mammogram, ultrasound, MRI, or special mammography views. Your doctor may order a breast biopsy if an abnormality is detected on a physical exam. If a breast biopsy is indicated, there are different methods of obtaining the tissue sample. You can have it performed by doing a stereotactic needle biopsy using mammography guidance, an ultrasound-guided core biopsy, or an MRI-guided biopsy to ascertain whether a malignancy (cancer) is present. The preferred method is determined by which imaging the abnormality is best visualized, the size of the lesion, the location of the lesion in the breast, and the patient’s health status.

Today many suspicious breast abnormalities can be diagnosed without surgery by using needle biopsy. In the past, excisional surgery biopsy was the only option for this purpose.

There are two types of needle biopsies - fine needle aspiration biopsy (FNAB) and core needle biopsy (CNB). FNAB uses a very thin needle to remove fluid and tiny fragments of tissue. CNB uses a slightly larger needle to remove a cylindrical piece of tissue about 1/16 inch in diameter and 2 inches long. CNB is the preferred method because FNAB is difficult due to the small amount of tissue extracted maybe inadequate. In our center, the core needle biopsy is the preferred choice.

Even if an abnormality is too small to be felt, FNAB or CNB can still be done using breast imaging methods such as ultrasound, stereotactic mammography, and MRI to guide the needle into the lesion.

What is a Stereotactic Needle Biopsy?  

Stereotactic needle biopsy is a method that is useful in some cases in which calcifications or a mass can be seen on a mammogram but cannot be located by touch. Based on mammograms taken from two angles, computerized equipment maps the precise location of the mass or calcifications. The computer guides the placement of the needle for core needle biopsy.

Wire localization is a procedure used to guide a surgical (excisional) breast biopsy of a small lump that is difficult to locate by touch or of areas that look suspicious on the x-ray (due to calcifications, for example) but do not have a distinct lump. After numbing the area with local anesthetic, a hollow needle, thinner than that used for drawing blood, is placed into the breast and x-ray pictures are taken to guide the needle to the suspicious area. A thin wire is inserted through the center of the needle. A small hook at the end of the wire keeps it in place. The hollow needle is then removed, and the surgeon uses the wire as a guide to locate the abnormal area to be removed.

What is an Ultrasound-Guided Breast Biopsy?

Ultrasonography uses sound waves at very high frequency to image internal structures, including those deep within the body. Either pulsed or continuous sound waves are directed at the area of interest using a hand-held device called a transducer. The transducer also receives echoes of the sound waves in a pattern that reflects the outlines of the internal structure mass. The transducer changes electrical signals into ultrasound waves and converts the reflected sound waves back to electrical energy. Unlike radiological procedures, the ultrasound method requires no exposure to x-rays.

An ultrasound-guided breast biopsy can be performed when a breast ultrasound shows an abnormality such as:

  • a suspicious solid mass
  • a distortion in the structure of the breast tissue
  • an area of abnormal tissue change

There are times when your doctor may decide that ultrasound guidance for biopsy is appropriate even for a mass that can be felt.

Ultrasound guidance is used in four biopsy procedures:

  • fine needle aspiration (FNA), which uses a very small needle to extract fluid or cells from the abnormal area.
  • core needle biopsy (CNB) which uses a large hollow needle to remove one sample of breast tissue per insertion.
  • vacuum-assisted device (VAD) which uses a vacuum powered instrument to collect multiple tissue samples during one needle insertion.
  • wire localization, in which a guide wire is placed into the suspicious area to help the surgeon locate the lesion for surgical biopsy.

You will be positioned lying face up on the examination table or turned slightly to the side. A local anesthetic will be injected into the breast to numb it. Using an ultrasound probe to visualize the location of the breast lump, the radiologist inserts a biopsy needle through the skin, advances it into the mass and removes tissue samples. If a surgical biopsy is being performed, ultrasound may be used to guide a wire directly into the mass to help the surgeon locate the area for excision. With continuous ultrasound imaging, the physician is able to view the biopsy needle or wire as it advances to the location of the lesion in real-time.

A small marker may be placed at the site so that it can be located in the future if necessary.

Once the biopsy is complete, pressure will be applied to stop any bleeding and the opening in the skin is covered with a dressing. No sutures are needed.

A mammogram may be performed to confirm that the marker is in the proper position.

This procedure is usually completed within an hour.

What is MRI-Guided Breast Biopsy?

When the breast lesion cannot be seen with mammography or ultrasound, and can only be seen using Magnetic Resonance Imaging (MRI), MRI is used to help guide the radiologist’s instruments to the site of the abnormal growth.

Using MRI guidance to calculate the position of the abnormal tissue and to verify the placement of the needle, the radiologist inserts the biopsy needle through the skin, advances it into the lesion and removes tissue samples. If a surgical biopsy is being performed, MRI may be used to guide a wire into the mass to help the surgeon locate the area for excision.

The choice of which type of breast biopsy to use will depend on each patient's situation, which modality the lesion is best seen, as well as their needs. Some of the factors to consider include how suspicious the lesion appears, how large it is, where in the breast it is located, the lesion type, how many lesions are present, other medical problems the patient may have, and personal preferences. Patients are encouraged to discuss the advantages and disadvantages of different biopsy types with their doctors.

What to expect when you need to have a breast biopsy:


When you arrive we will give you a detailed explanation specific to your procedure, and we will ask you to sign a consent form. You will be asked to change into a gown. Once you are in the proper position, your skin will be cleaned and numbed.

The method differs somewhat for each modality.

  • Stereotactic biopsy You will lie face down on a special table. The technologist will help you get in a position to ensure your optimal comfort. The breast of concern is positioned by the technologist and the procedure is performed by the radiologist. The radiologist is guided by taking X-rays of your breast while you are lying on the table.
  • Ultrasound-guided biopsy You will lie on your back on a padded table, with the arm of the affected side resting on a pillow over your head. The technologist will scan your breast with an ultrasound probe to localize the suspicious area, and the radiologist will then perform the biopsy.
  • MRI-guided biopsy You will lie face down, and be placed into a specialized radio-frequency coil. Contrast medium will be injected into a vein in your arm and an MRI scan will be done to localize the area for the radiologist. Once the area is precisely located, the biopsy procedure will be performed.

Frequently, after tissue samples have been removed, a tiny marker particle called a “clip” is left inside your breast to identify the biopsy site. If a “clip” is inserted into the biopsy site, a mammogram will be taken after the biopsy to document its placement.

When the biopsy is over, the technologist will hold pressure on the biopsy site for 10 minutes to stop any bleeding. The site will be dressed with gauze and surgical tape, and an ice pack will be placed on it to reduce swelling and bruising.

We then send the tissue sample to the pathologist who will issue a report to us and to your doctor, usually within 24 hours.