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 give 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?

 If you are on blood thinners or take aspirin, your provider may want you to 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 area being tested.
• Sometimes a small cut in the skin is made before the biopsy needle is put in.
• 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 a few 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 insertion and removal of the needle only takes about 1 minute, but the whole biopsy takes about 15 to 30 minutes.

Is imaging used during the core needle biopsy?

If the lesion or mass can be felt by your provider, then often 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?

Your care team may ask you not to do any 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 called a hematoma can 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 get 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 all of their findings. Your provider will talk with you about your results.