Breast Biopsy

What is a breast biopsy?

A biopsy is a tiny piece of tissue or fluid (called a sample) that's taken out for testing. A biopsy is often needed to find the cause of a change in breast tissue.

For a breast biopsy, breast tissue may be removed with a special biopsy needle. Sometimes the tissue is removed during surgery. The tissue that's taken out is sent to a lab. There, it's tested to see if there are cancer or other abnormal cells in it.

Why might I need a breast biopsy?

A breast biopsy may be done:

  • To learn more about a lump or mass that can be felt in the breast

  • To check a problem seen on a mammogram, such as small calcium deposits in breast tissue (microcalcifications) or a fluid-filled mass (cyst)

  • To evaluate nipple changes, such as a bloody discharge from the nipple

  • To find out if a breast lump or mass is cancer (malignant) or not cancer (benign)

A lump or other area of concern in the breast may be caused by cancer. But it might also be caused by another, less serious, problem. Many times, a biopsy is the only way to know for sure.

There may be other reasons for your healthcare provider to recommend a breast biopsy. Ask why they think a biopsy is needed and what the process will be like.

Types of breast biopsies

There are many ways to do a breast biopsy. The type of biopsy you'll have depends on where the breast lump or changed tissue is, what the change looks like on mammogram or ultrasound, how big it is, and your preferences.

Biopsies may be done under local or general anesthesia. For local anesthesia, medicine is used to numb your breast. You'll be awake, but won't feel pain. For general anesthesia, you'll be given medicine to put you into a deep sleep so you don't feel pain during the biopsy. 

Common types of breast biopsies include:

  • Fine needle aspiration (FNA) biopsy. A very thin, hollow needle is put through your skin and into the lump or area of concern. A syringe is used to take out a small sample of fluid or cells. No cut (incision) is needed. There's rarely a scar. An FNA biopsy may be done to help see if the area is a fluid-filled sac (cyst) or a solid lump.

  • Core needle biopsy. This biopsy takes out more tissue than an FNA biopsy. The breast is numbed. Then the provider guides a large, hollow needle through the skin into the lump or area of concern. Small cylinders of tissue, called cores, are removed. They're about the size of a grain of rice. You may have a bruise, but no cut or stitches are needed. Scarring is uncommon.

  • Open (surgical) biopsy. This type of biopsy might be done if the results of a needle biopsy aren't clear. A cut is made in the breast. Part or all of the lump or changed area is removed for testing. This biopsy may leave a scar. When part of the lump is removed, it's called an incisional biopsy. Removing all of the lump is called an excisional biopsy.

    In some cases, the lump may be small, deep, and hard to find. Then a method called wire localization may be used. For this, the surgeon puts a thin needle with a very thin wire inside it into the breast. An imaging test (like a mammogram or ultrasound) helps guide the tip of the needle into the lump. The needle is then taken out but the wire stays in. The surgeon then follows this wire to find the lump and take it out. Other localization methods involve putting tiny magnetic or radioactive pellets in the lump. Again, imaging tests are used to guide the needle so the pellets are put in the right place. During surgery, a tool is used to find the pellets and take out the right piece of breast tissue.

Sometimes special tools and methods are used to guide the needles and help with biopsy procedures. Some of these include:

  • Stereotactic biopsy. With this method, a 3-D image of the breast is made using a computer and mammogram results. The image is used to guide the biopsy needle to the exact site of the breast lump or area of concern.

  • Vacuum-assisted core biopsy. To do this, a small cut is made in the breast. The provider puts a hollow tube (probe) into the breast through the cut. It's guided to the breast change using MRI, X-rays, or ultrasound. Suction is then used so the breast tissue is gently pulled into the probe. A spinning knife inside the probe cuts the tissue from the breast. Many tissue samples can be taken from this one cut.

  • Ultrasound-guided biopsy. This method uses ultrasound images of the breast lump or change. These images help guide the needle to the exact biopsy site.

What are the risks of a breast biopsy?

All procedures have some risk. Some possible complications of a breast biopsy include:

  • Bruising and mild pain at the biopsy site

  • Prolonged bleeding at the biopsy site

  • Infection near the biopsy site

Risks depend on the type of biopsy that's done. For instance, if a lot of tissue is removed during a surgical biopsy, the shape of your breast may change.

If the biopsy is done using an X-ray or mammogram, the amount of radiation used is small. The risk for radiation exposure is very low.

You may have other risks depending on your overall health. Be sure to discuss any concerns with your healthcare provider before the biopsy is done.

How do I get ready for a breast biopsy?

Your provider will explain the procedure to you. Ask any questions you have so you know what to expect.

  • You'll be asked to sign a consent form that gives your permission to do the procedure. Read the form carefully and ask questions if anything isn't clear.

  • Tell your provider if you are pregnant or think you may be pregnant.

  • Tell your provider if you are sensitive to or allergic to any medicines, latex, tape, and anesthesia medicines (local and general).

  • Tell your provider about all the medicines you take. This includes both over-the-counter and prescription medicines. It also includes vitamins, herbs, and other supplements, as well as marijuana or CBD.

  • Tell your provider if you have a history of bleeding disorders. Let your provider know if you are taking any blood thinners, aspirin, ibuprofen, or other medicines that affect blood clotting. You may need to stop taking these for a few days before the biopsy.

  • In most cases, if your breast is going to be numbed (local anesthesia) but you will be awake, you don’t need to prepare for a biopsy. But if you're given medicine to put you into a deep sleep (general anesthesia), you won't be able to eat or drink anything for some time before the surgery. You'll be given detailed instructions.

  • Don’t use lotion, cream, powder, deodorant, or perfume on your arm, underarm, or breast on the day of the procedure.

  • If you get a sedative or general anesthesia, make sure you have someone to drive you home afterward. You will not be able to drive after the biopsy.

  • Your healthcare provider may have other instructions for you based on your medical condition.

What happens during a breast biopsy?

A breast biopsy may be done in a provider’s office. It's often done on an outpatient basis, which means you go home the same day. Sometimes it's done during a hospital stay. Some types of biopsies only need local anesthesia. For other types, general anesthesia is needed. Procedures vary a lot.

For the most part, a needle breast biopsy follows this process:

  1. You'll be asked to remove any clothing from the waist up. You'll be given a gown to wear. You might also be asked to remove all jewelry, glasses, and dental appliances.

  2. You may lie down or sit up. It depends on your provider’s preference and if imaging guidance will be used and what type.

  3. The skin over the biopsy site will be cleaned with a sterile solution.

  4. When a local anesthetic is used, you'll feel a needle stick when the medicine is injected. You may feel stinging when the medicine is put in. The biopsy will not start until the area is numb.

  5. When ultrasound is used, the provider will move the probe over your breast to find the breast lump or change.

  6. When stereotactic imaging is used, you'll lie face down with your breast placed in an opening on the table. A computer will find the exact site of the breast lump or area of concern.

  7. You will need to stay very still during the biopsy. But you won’t need to hold your breath. 

  8. The provider will put the needle through your skin into the biopsy site or through a tiny cut (incision). A small sample of tissue or fluid will be taken out. You may feel pressure when suction is used to take out the sample.

  9. A tiny marker or clip might be put in to mark the biopsy site. This marker shows up on imaging tests so the exact area can be found if more treatment is needed or for follow-up monitoring.

  10. Pressure will be applied to the biopsy site until the bleeding stops.

  11. If needed, the opening will be closed with stitches or strips of tape.

  12. A sterile bandage or dressing will be used to cover the site.

  13. The tissue sample(s) will be sent to the lab.

Generally, an open or surgical breast biopsy will follow this process:

  1. You'll be asked to remove your clothing and will be given a gown to wear. You'll also be asked to remove all jewelry, glasses, and dental appliances.

  2. In some cases, an imaging test will be used to guide a thin wire into the lump before the biopsy. This is to help the healthcare provider find the breast lump or mass. Other X-ray-guided methods may be used, too.

  3. An IV (intravenous) line may be put in a vein in your arm or hand.

  4. You'll be placed on an operating table.

  5. Medicine (a sedative) may be put in your IV to relax you.

  6. If local anesthesia is given, you'll feel a needle stick to numb your breast tissue.

  7. If general anesthesia is given, the anesthesiologist will keep checking your heart rate, blood pressure, breathing, and blood oxygen level during the surgery.

  8. The skin over the surgical site will be cleaned with a sterile solution.

  9. The provider will make a small cut in your skin and underlying breast tissue until the lump or mass is exposed.

  10. Part or all of the lump will be removed.

  11. Pressure will be applied to the biopsy site until the bleeding stops.

  12. The opening will be closed with stitches or strips of tape.

  13. A sterile dressing or bandage will be applied.

  14. The tissue will be sent to the lab for testing.

What happens after a breast biopsy?

How long it takes to recover will depend on the type of biopsy you had and the type of anesthesia used.

If you had general anesthesia, you'll be taken to the recovery room where you'll be watched closely. Once your blood pressure, pulse, and breathing are stable and you're alert, you'll be taken to your hospital room. Or you will go home. If the biopsy was done on an outpatient basis, you should plan to have another person drive you home.

If you had local anesthesia, you'll be able to go home after you have recovered.

At home

Follow all instructions from your healthcare team. Keep the biopsy area clean and dry. If stitches were used, they'll be removed during a follow-up office visit. Your healthcare team will tell you when you may remove the bandage or dressing. They'll also tell you when you can bathe as normal.

The biopsy site may be sore for a few days. Take a pain reliever as recommended by your provider. Aspirin or certain other pain medicines may increase your chance of bleeding. So be sure to take only recommended medicines. Wearing a supportive bra may help.

You may go back to your normal diet unless your provider tells you differently. You may be told not to do any strenuous physical activity for a few days.

Call your healthcare provider if you have any of the following:

  • Fever or chills

  • Redness, swelling, bleeding, or other drainage from the biopsy site

  • Increased pain around the biopsy site

Your healthcare provider may give you other instructions. Be sure you understand what to do. Ask how to contact your healthcare team on weekends, evenings, and holidays.

Getting your biopsy results

It usually takes several days for the results of your biopsy to come back. This can be a scary and anxious time. Talk with your provider about when and how you can expect to get your biopsy results. Ask if you will receive a phone call or if you need to make an appointment.

Next steps

Before you agree to a test or procedure, make sure you know:

  • The name of the test or procedure

  • The reason you are having the test or procedure

  • What results to expect and what they mean

  • The risks and benefits of the test or procedure

  • What the possible side effects or complications are

  • When and where you are to have the test or procedure

  • Who will do the test or procedure and what that person’s qualifications are

  • What would happen if you did not have the test or procedure

  • Any alternative tests or procedures to think about

  • When and how you will get the results

  • Who to call after the test or procedure if you have questions or problems

  • How much you will have to pay for the test or procedure