What Is Fine Needle Aspiration for Breast Biopsy?

This test is used to determine the status of a breast lump

After a breast lump is found, more tests are needed to determine what the lump means and if it is cancerous or not. Fine needle aspiration (FNA) is a procedure used to obtain a sample of cells from a breast lump. The results help determine whether it’s a cyst, an infection, a benign tumor, or cancer.

FNA is usually chosen when a lump is likely a fluid-filled cyst. This is because the procedure is particularly helpful in distinguishing cysts from solid masses. Your healthcare provider will use a very fine needle (much smaller than a blood draw needle) to extract some fluid, which will be examined under a microscope by a pathologist.

This article will review FNA in detail and go over what you might be able to expect when undergoing FNA.

fine needle aspiration
 Verywell / Emily Roberts

Purpose of Test

Getting any breast lump checked out is a wise move. Having a fine needle aspiration may seem scary, but it’s a safe, minor procedure that provides clear information about a potentially suspicious lump.

If the lump turns out to be a cyst—a harmless, fluid-filled sac—the fluid can be drained out at the same time, relieving any pressure it may be causing.

About 80% of breast lumps are not cancerous, but a small percentage of them are malignant. In either case, the examination of the fluid from the aspiration can give your healthcare provider enough information to determine what the next steps should be.

There are two main advantages of FNA, according to the American Cancer Society: One is that the skin doesn’t have to be cut, so there’s no need for stitches and no scar. The other is that, in some cases, it’s possible to make a diagnosis the same day.

Risks and Contraindications

Risks with FNA are minimal. There’s a slight chance of bleeding and infection at the injection site. You might be sore for a day or two after the procedure and experience some mild bruising and swelling.

Before the Test

There’s little you need to do to prepare for fine needle aspiration, but the following information may be helpful to know in advance of the procedure.

Timing

It takes about 10 to 20 seconds to obtain each sample, and multiple samples may be taken. The whole procedure from start to finish usually takes no more than half an hour, but you should allow time for filling out forms and waiting in the office.

You can expect results within two to three days of the test, possibly sooner.

Location

Fine needle aspiration is an outpatient procedure performed in a healthcare provider’s office or a medical clinic that has professionals trained in the technique and access to a pathology lab that can examine the fluid collected.

If ultrasound guidance is needed, the biopsy is usually done in a radiology department. This machine, which uses high-frequency sound waves to provide an ongoing image of the lump, enables the healthcare provider to guide the needle to exactly the right spot.

Food and Drink

You’re able to eat and drink normally before the procedure. Ask your healthcare provider whether you should stop taking any medicines before the procedure, such as blood thinners.

Cost and Health Insurance

Most private insurers, as well as Medicare, cover the cost of a breast biopsy when indicated. With some insurance companies, or when special techniques are recommended, you may need to obtain prior authorization.

Other Considerations

You won’t be put to sleep during FNA, so you will be able to go about your life—return to work, take care of your family, drive a car—after having the procedure.

During the Test

You will interact with the physician performing the fine needle aspiration, but not the pathologist who will examine the sample and, ultimately, deliver the results to your provider.

Pre-Test

You’ll undress from the waist up and wear a robe that opens in the front. After changing out of your clothes and before the procedure begins, your healthcare provider will ask if you have any questions. You will also be asked to sign an informed consent form, indicating you understand the purpose of the procedure and any potential risks.

You’ll be awake during the procedure and positioned on your back. Your skin will be swabbed with an antiseptic solution to prevent infection.

You can ask for a local anesthetic to numb the area of your breast that the needle will enter, but the needle used for FNA is so fine that getting an anesthetic might hurt more than the biopsy itself.

Throughout the Test

Your healthcare provider will locate the lump by feeling it or by using ultrasound to see it. Then, they will immobilize the lump and use a very thin needle to pierce it and draw out fluid with a syringe. If ultrasound is used, you may feel some pressure from the wand as the needle is inserted.

If no fluid comes out, the healthcare provider may reposition the needle and try again.

Post-Test

Once the fluid is captured, the needle is removed, pressure is applied to prevent a bruise, and a bandage is used to cover the site.

After the Test

When performed by an experienced practitioner, fine needle aspiration is virtually free of significant complications.

The most common ones are slight bruising, tenderness, or swelling of the area for a few days following the procedure. These can be relieved with over-the-counter pain relievers like Tylenol (acetaminophen) and by applying cold compresses for short periods of time.

Call your healthcare provider if you experience continued swelling or bleeding, a fever above 101 F, and/or unrelenting pain.

Interpreting Results

A specially trained doctor called a pathologist will look at the biopsy fluid or tissue to see if it contains cancer cells. Test results can take up to two or three days, though sometimes they’re available the same day. The pathology report will be sent to your healthcare provider, who will call or have you come in to get the results.

  • A normal result means there’s no sign of cancer or other breast problems.
  • An abnormal result doesn’t mean you have cancer or precancer, but perhaps any number of benign breast conditions, including a fibroadenoma or fat necrosis.

The color of the fluid drawn out of the lump during the procedure will give some clues about its nature:

  • If the fluid is brown, green, or tan, and the lump shrinks as a result of the aspiration, it’s most likely a cyst.
  • Sometimes the fluid will be clear or bloody, and in rare cases this will mean the lump is cancerous.
  • If the needle draws out small bits of tissue and very little fluid it, that indicates a solid mass.

Needle aspiration is 80% to 85% accurate in giving a clear indication as to whether a breast lump is a cyst or a solid breast mass. Sometimes, though, the results don’t give a clear diagnosis.

Fine needle aspiration may result in draining a cyst, causing the lump to go away. This is a good indication that the lump was not cancerous. However, some cysts do refill and, if they become bothersome, can be surgically removed.

Follow-Up

The pathology report will help you and your healthcare provider talk about the next steps, if any. If your healthcare provider still has concerns for some reason, they may recommend doing another FNA or another type of biopsy, such as:

  • Core needle biopsy: This requires the use of a larger needle than a fine needle biopsy and removes a small cylinder (“core”) of tissue, rather than a collection of cells. It’s often done using ultrasound or magnetic resonance imaging (MRI) to help locate the right area for the biopsy.
  • Stereotactic biopsy: With this method, a 3D image of the breast is made using a computer and mammogram results. The 3D image then guides the biopsy needle to the exact site of the breast lump.
  • Open (surgical) biopsy: This type of biopsy may be incisional (involving the removal of part of the abnormality) or excisional (removing all of the abnormality).

If it’s breast cancer, you will likely be referred to a breast cancer specialist, who may recommend more scans, lab tests, or surgery. Your medical team will use the pathology report and the results of the other tests to determine the stage of cancer and to design the best treatment plan for you.

Summary

Hearing that you need a biopsy to get more information about a breast lump can be unsettling. But a fine needle aspiration is minimally invasive and can provide valuable information about your lump. It is a short procedure with few side effects which can be done fairly easily. Talk with your healthcare provider about any questions or concerns you may have about the procedure or what to expect.

A Word From Verywell

Undergoing, waiting for, and receiving test results can be anxiety provoking. But keep in mind that 80% of women who have a breast biopsy do not have breast cancer. Even if a cancer is found, the majority of these cancers will be early-stage tumors.

Treatment of these cases has improved, with newer options significantly reducing the risk of recurrence and often being far less invasive than older ones. As for metastatic cases, which is present in less than 5% of women at the time of diagnosis, treatments are improving and life expectancy is increasing.

Frequently Asked Questions

  • Is fine needle aspiration used only for breast biopsies?

    No. Fine needle aspiration can be used anywhere on the body. It is most commonly used on the breast, the thyroid, suspicious lymph nodes, or skin masses.

  • Is fine needle aspiration of the breast painful?

    It shouldn’t be. The needle is so thin, causing so little pain (if any) that local anesthetic is generally not even needed.

  • Is fine needle aspiration the same as a biopsy?

    Yes, it is a type of biopsy. In a biopsy, cells, fluid, or tissue is removed and examined. In FNA, the fluid and cells are removed via the needle and subsequently examined.

  • What percentage of biopsies are cancer?

    About 20% of breast biopsies turn out to be cancer. This means that the vast majority of breast cancer biopsies do not reveal cancer. This can be helpful to remember if you are feeling anxious.

Originally written by
Pam Stephan
Pam Stephan is a breast cancer survivor.
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11 Sources
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