Core biopsy

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A core biopsy removes tissue from the body using a hollow needle. The tissue is then looked at under a microscope. A core biopsy is sometimes called a core needle biopsy.

The tissue removed during a core biopsy comes out as one long, narrow piece (called a core). The structure of the tissue remains intact, so doctors can see what the tissue around the cancer looks like. This gives them information that helps them decide whether to recommend further tests or treatment.

A core biopsy can be done on most areas of the body, but it is most often used to remove tissue from an abnormal area of the breast, prostate, liver, lung or lymph nodes.

Why a core biopsy is done

Your doctor may do a core biopsy if they find a lump or abnormal area during a physical exam or on an imaging test, such as an x-ray or ultrasound. Sometimes doctors need to do a core biopsy after a fine needle aspiration to confirm a diagnosis.

A core biopsy is used to:

  • check for cancer
  • find out the type of tumour
  • find out the grade of cancer

How a core biopsy is done

A core biopsy is done in a doctor's office, clinic or hospital as an outpatient procedure (you won't need to stay overnight). You usually don't need to take any steps in advance to prepare for it, but your healthcare team will tell you if you do. The entire procedure takes about 15 to 30 minutes. The part that involves using the needle and removing the tissue is very quick and takes about a minute.

During the test, you will sit or lie down. After numbing the area with a local anesthetic, the doctor will take several samples of tissue from it using a hollow needle. The tissue is sent to a lab to check for abnormal cells.

If the doctor can feel the lump, they can use a physical exam to help guide the needle. If they can’t feel the lump, the doctor will use 3D imaging (ultrasound, MRI or CT scan) or x-ray to help guide the needle.

Special types of core biopsy

Stereotactic core-needle biopsy and vacuum-assisted core biopsy are special types of core biopsy.

Stereotactic core-needle biopsy

This type of biopsy takes samples using 3D imaging to find the exact location of the abnormal area. This is done when a doctor can't feel the area that needs to be biopsied. The doctor uses 3D imaging to help guide the needle during the biopsy. Sometimes a small piece of metal is placed in the area so that it can be easily found if the doctor must look at it later. A stereotactic core biopsy is usually used to diagnose types of brain and breast cancer.

Learn more about stereotactic core biopsy.

Vacuum-assisted core biopsy

This type of core biopsy is helped by suction from a vacuum device. It can remove multiple samples of tissue with only one needle insertion. The doctor makes a small cut (incision) in the skin for the needle to enter through. They may use x-rays, an ultrasound or an MRI to guide the needle through the cut into the area. A rotating knife inside the needle cuts the tissue and the vacuum pulls it inside the needle.

A vacuum-assisted core biopsy is most often used to diagnose breast cancer.

Side effects

Side effects of a core biopsy depend on the part of the body where the biopsy is done. For example, someone who has a core biopsy of the prostate will have different side effects than someone who has a core biopsy of the breast. In general, side effects may include:

  • bleeding or bruising
  • tenderness
  • swelling
  • pain
  • infection (red, warm or painful skin following the procedure)

Depending on where you had the biopsy, you may need to avoid heavy physical activity for 1 or 2 days after the procedure. Sometimes a vacuum-assisted core biopsy leaves a small scar.

What the results mean

A pathologist will check the sample for abnormal cells. They will give you a pathology report based on what they found. The pathology report describes the types of cells in the sample, what they look like and if they contain cancer.

If the results are abnormal, your doctor may recommend more tests, procedures, follow-up care or treatment.

Special considerations for children

Preparing children before a test or procedure by explaining what will happen during a test, such as what the child will see, feel and hear, can be very helpful. Preparing children before a test or procedure can help lower their anxiety, make them more cooperative and develop their coping skills.

Preparing a child for a core biopsy depends on the age and experience of the child. Find out more about helping your child cope with tests and treatments.

Expert review and references

  • Anita Bane, MB, MRCPI, FRCpath, PhD

Medical disclaimer

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