Core Needle Biopsy

A core needle biopsy is a medical test to remove a piece of tissue from a lesion or mass. The tissue is then tested to find out what it is. A core needle biopsy can remove more tissue than a fine needle biopsy. Because of this, it can provide more information about the cells and tissue removed.

When are core needle biopsies used?

A core needle biopsy can be used on most parts of the body. The most common are:

• Breast.
• Prostate.
• Bone.
• Lymph nodes.
• Thyroid nodules.

How do I prepare for a core needle biopsy?

No preparation is needed for this test. However, if you are on blood thinners or take aspirin your provider may have you stop taking them for a few days before the test.

How is this test done?

Core needle biopsies are done as an outpatient procedure (you will not stay overnight). Here is what you can expect during the test:

• You will be lying or sitting, and you will need to hold still for the test.
• Local anesthesia, such as lidocaine (numbing medicine), is used to numb the testing area.
• Sometimes a small cut is made in the skin before the biopsy needle is inserted.
• The needle (about the size of a needle used to draw blood) is then put into the area being tested, and tissue is removed. This may be done several times to make sure enough tissue is removed for testing.
• Stitches are not usually needed, but a bandage will be placed over the cut.

The actual insertion and removal of the needle takes about 1 minute, but the entire biopsy takes about 15-30 minutes.

Is imaging used during the core needle biopsy?

If the lesion or mass can be felt by your provider, then typically no imaging is needed for the biopsy. If the lesion or mass can’t be felt then an ultrasound, x-ray, or CT scan can be used to help find the area to biopsy. If mammogram images are used during the biopsy it is called stereotactic needle biopsy. If ultrasound imaging is used with core needle biopsy it is called ultrasound guided needle biopsy.

What can I expect after the core needle biopsy?

You may be asked to limit heavy activity for a day or two. Once the numbing medication wears off, you may have some discomfort. You may also have bruising, swelling, or a small amount of bleeding at the site of the biopsy.

In some cases, a pocket of blood, or a hematoma, will collect at the site of the biopsy. This can be uncomfortable but should get better over the next few days. If you have severe pain, you should call your provider right away.

How do I receive the results of my core needle biopsy?

The tissue sample is reviewed by a pathologist and a report is written. The report will give your provider information about normal and not normal findings. Your provider will discuss your results with you.