If breast symptoms or the results of an imaging test (such as a mammogram) suggest you might have breast cancer, you may need a breast biopsy. During a biopsy, a doctor removes small pieces of breast tissue from the suspicious area so they can be looked at in the lab to see if they contain cancer cells.
Needing a breast biopsy doesn’t necessarily mean you have cancer. Most biopsy results are not cancer, but a biopsy is the only way to find out for sure.
There are different kinds of breast biopsies. Some are done using a hollow needle, and some use an incision (cut in the skin). The type you have depends on a number of things, like:
Most of the time, a needle biopsy (rather than a surgical biopsy) can be done. Ask your doctor which type of biopsy you will have and what you can expect during and after the procedure.
For a fine needle aspiration (FNA), a very thin, hollow needle attached to a syringe is used to withdraw (aspirate) a small amount of tissue or fluid from a suspicious area.
A core needle biopsy (CNB) uses a larger hollow needle to sample breast changes felt by the doctor or seen on an ultrasound, mammogram, or MRI. This is often the preferred type of biopsy if breast cancer is suspected.
In rare cases, surgery is needed to remove all or part of the lump for testing. This is called a surgical or open biopsy. Most often, the surgeon removes the entire mass or abnormal area as well as a surrounding margin of normal breast tissue.
This type of biopsy might be done to check the lymph nodes under the arm for cancer spread. This might be done at the same time as a biopsy of the breast tumor, or when the breast tumor is removed during surgery. Checking the lymph nodes can be done by core needle biopsy, or with a sentinel lymph node biopsy (SLNB) and/or an axillary lymph node dissection.
Regardless of which type of biopsy you have, the biopsy samples will be sent to a lab where a doctor called a pathologist will look at them. It typically will take at least a few days for you to find out the results.
It’s important to ask questions if there’s anything you’re not sure about. Here you can find a detailed list of questions to ask your doctor before getting a breast biopsy.
If the doctor doesn't think you need a biopsy, but you still feel there’s something wrong with your breast, follow your instincts. Don’t be afraid to talk to the doctor about this or go to another doctor for a second opinion. If possible, try to see someone who specializes in breast health to discuss your concerns. A biopsy is the only sure way to diagnose breast cancer.
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.
Last Revised: January 14, 2022
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