Surgical Breast Biopsy

If other tests show you might have breast cancer, your doctor may refer you for a breast biopsy. Most often this will be a core needle biopsy (CNB) or a fine needle aspiration (FNA) biopsy. But in some situations, such as if the results of a needle biopsy aren’t clear, you might need a surgical (open) biopsy. During this procedure, a doctor cuts out all or part of the lump so it can be checked for cancer cells.

What is a surgical biopsy?

For this type of biopsy, surgery is used to remove all or part of a lump so it can be checked to see if there are cancer cells in it.

There are 2 types of surgical biopsies:

  • An incisional biopsy removes only part of the abnormal area.
  • An excisional biopsy removes the entire tumor or abnormal area. An edge (margin) of normal breast tissue around the tumor may be taken, too, depending on the reason for the biopsy.

Preoperative localization to guide surgical biopsy

If the change in your breast can’t be felt and/or is hard to find, a mammogram, ultrasound, or MRI may be used to place a wire or other localizing device (such as a radioactive or magnetic seed, or a radiofrequency reflector) into the suspicious area to guide the surgeon the right spot. This is called preoperative localization (or stereotactic wire localization if a wire is used).

For wire localization, your breast is numbed, and an imaging test is used to guide a thin, hollow needle into the abnormal area. Once the tip of the needle is in the right spot, a thin wire is put in through the center of the needle. A small hook at the end of the wire keeps it in place, while the other end of the wire remains outside of the breast. The needle is then taken out. You then go to the operating room with the wire in your breast. The surgeon uses the wire as a guide to the area to be removed. When this method is used, it is done the same day as your surgery.

In newer methods of localization, a localizing device is put into the suspicious area before the day of your surgery, so you don’t have to have it done the morning of your operation. Radioactive or magnetic seeds (tiny pellets that give off a very small amounts of radiation or that create small magnetic fields) or radiofrequency reflectors (small devices that give off a signal that can be picked by a device held over the breast) can be placed completely inside the breast (unlike the wire used for wire localization). Your surgeon can then find the suspicious area by using a handheld detector in the operating room.

What should you expect if you have a surgical biopsy?

During a surgical biopsy

Rarely, a surgical biopsy might be done in the doctor's office. But most often it's done in a hospital’s outpatient department. You are typically given local anesthesia with intravenous (IV) sedation. (This means you’re awake, but your breast is numbed, and you’re given medicine to make you drowsy.) Another option is to have the biopsy done under general anesthesia (where you’re given medicine to put you in a deep sleep and not feel pain).

The skin of the breast is cut, and the doctor removes the suspicious area. You often need stitches after a surgical biopsy, and pressure may be applied for a short time to help limit bleeding. The area is then covered with a sterile dressing.

After a surgical biopsy

The biopsy can cause bleeding, bruising, or swelling. This can make it seem like the breast is larger after the biopsy. Most often, this is nothing to worry about, and the bleeding, bruising, and swelling go away over time. Your doctor or nurse will tell you how to care for the biopsy site and when you might need to contact them if you’re having any issues.

A surgical biopsy may leave a scar. You might also notice a change in the shape of your breast, depending on how much tissue is removed.

What does a surgical biopsy show?

A doctor called a pathologist will look at the biopsy tissue under a microscope to find out if there are cancer cells in it.

Ask your doctor when you can expect to get the results of your biopsy. The next steps will depend on the biopsy results.

If no cancer cells are found in the biopsy, your doctor will talk to you about when you need to have your next mammogram and any other follow-up visits.

If cancer is found, the doctor will talk to you about the kinds of tests needed to learn more about the cancer and how to best treat it. You might need to see other doctors, too.

The American Cancer Society medical and editorial content team

Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.

Chagpar AB. Techniques to reduce positive margins in breast-conserving surgery. 2019. UpToDate. Accessed at www.uptodate.com/contents/techniques-to-reduce-positive-margins-in-breast-conserving-surgery on September 24, 2019.

Joe BN, Esserman LJ. Breast Biopsy. 2019. UpToDate. Accessed at www.uptodate.com/contents/breast-biopsy on August 26, 2019.

Last Medical Review: September 1, 2017 Last Revised: October 9, 2017

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