The Who, What, Where, When and Sometimes, Why.

Fine Needle Aspiration (Fine Needle Biopsy) Procedure

Fine needle aspiration (also called fine needle biopsy or FNA) removes cells from a suspicious lump in the breast. The needle used is thinner than in core needle biopsy.

Fine needle aspiration is only used for lumps in the breast that can be felt (palpable masses).

Core needle biopsy is the standard and preferred way to biopsy palpable breast masses. However, fine needle aspiration is sometimes done as a quick way to sample a breast lump or suspicious lymph nodes in the underarm area.

Learn more about types of breast biopsies.

The procedure

A fine needle aspiration can be done in your health care provider’s office. The procedure is less invasive than a core needle biopsy and the chance of infection or bruising is very small.

Before the procedure, your health care provider may use a small amount of local anesthetic to numb the area.

Your health care provider will then insert the needle and remove a sample of cells.

The whole process only takes a few minutes.

What to expect

After a fine needle aspiration, you may feel sore in the biopsy area. Placing an ice pack on the area, resting, or taking a mild pain reliever such as ibuprofen (Advil or Motrin), naproxen (Aleve or Naprosyn) or acetaminophen (Tylenol) may help.

You may also feel a buildup of emotions. You may be anxious leading up to the procedure. You might feel discomfort or distress during the procedure. And you may be worried about the results.

You may want to take the day off from work and other commitments to recover both physically and emotionally. You may also want to have a family member or friend go with you to the procedure and be available afterwards for support.

Find more ways to cope while you wait for your biopsy results.

Drawbacks of fine needle aspiration

One important drawback of fine needle aspiration is the cell samples give limited information about the tumor. For example, the pathologist can’t tell whether a tumor is non-invasive breast cancer (ductal carcinoma in situ) or invasive breast cancer from the samples.

With both fine needle aspiration and core needle biopsy, the needle can miss a tumor and take a sample of normal cells instead.

If this happens, the biopsy will show benign (not cancer) results, when in fact, cancer is present. This is called a false negative result and delays diagnosis. The false negative rate of fine needle aspirations of lumps that can be felt is low, about 2-4 percent [6,9-10].

Sometimes, even if the correct area is sampled, not enough cells are removed to be able to tell if there’s cancer. So, a fine needle aspiration that doesn’t find cancer may need to be followed up with a core needle biopsy or a surgical breast biopsy.

The cells removed by fine needle aspiration must also be checked by an experienced breast cytopathologist, and not all hospitals have one. 

Updated 06/23/23