Fine Needle Aspiration (FNA)

A fine needle aspiration (FNA) is a medical test that uses a thin needle to remove pieces of tissue from a cyst, lesion or tumor, or lymph nodes. The tissue is then tested to find out what it is, this is called a biopsy. For this test, there is no incision or cut in the skin. It is done by poking the skin with a needle. It is often well tolerated and can be done quickly.

When is FNA used?

The most common reason for FNA is to test for cancer. FNA can be used for almost any part of the body. Common locations are:

• Thyroid.
• Lymph nodes.
• Lung.
• Liver.
• Breast.
• Skin.

How do I prepare for a fine needle aspiration?

You may be asked not to eat or drink for several hours before the test. If you are on blood thinners or take aspirin, your provider may ask you to stop taking them a few days before the test.

How is this test done?

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

• The area of your skin where the test is being done with be made sterile by cleaning it.
• Numbing medication, if needed, will then be put into your skin to make the FNA less painful.
• Once the area is numb, a thin needle (one that is even smaller than the type used to draw blood) will be put into the skin in the area being tested. The needle may be placed several times to make sure enough tissue is removed to be tested.
• If your provider is unable to see or feel the lesion or mass and needs help finding the right area to biopsy, ultrasound, x-ray, or CT scan may be used.
• The actual insertion of the needle takes about 10-15 seconds. The entire FNA takes about 15-30 minutes.

What can I expect after my fine needle aspiration?

As the numbing medication wears off, you may have some discomfort. You may have swelling, soreness, and pain where the needle went in.

The main risk of an FNA is bleeding. A little bleeding where the needle went in is normal. But in some cases, a pocket of blood, called 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 fine needle aspiration?

Your tissue sample is reviewed under a microscope by a doctor called 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.