Bone marrow aspiration and biopsy

Bone marrow is the soft, spongy tissue inside most bones. Immature blood cells develop into red blood cells, white blood cells, and platelets in the bone marrow.

Bone marrow aspiration and biopsy are usually done together. A bone marrow aspiration removes a small amount of fluid and cells from the bone marrow. A bone marrow biopsy removes a small amount of bone along with fluid and cells from the bone marrow. The fluid, cells or bone removed during these procedures is examined under a microscope.

Why bone marrow aspiration and biopsy are done

These procedures are done to:

  • see if the bone marrow is making the normal number of blood cells
  • find out why blood counts are abnormal
  • diagnose blood disorders or conditions that affect the bone marrow
  • find infection that started in or has spread to the bone marrow
  • diagnose blood or bone marrow cancers, such as leukemia or multiple myeloma
  • find out if cancer from somewhere else in the body has spread to the bone marrow
  • check response to treatment for a bone marrow condition or cancer
  • collect a sample of bone marrow for medical procedures, such as stem cell transplant

How bone marrow aspiration and biopsy are done

These procedures are done in a clinic or hospital and usually take 20–30 minutes. Most people can go home after they are done. Very rarely, people will need to stay in the hospital.

Where doctors or nurse practitioners do a bone marrow aspiration and biopsy depends on your age. In adults, doctors or nurse practitioners usually take a bone marrow aspirate from the top of a hip bone (called the iliac crest) or sometimes from the breast bone (called the sternum). In babies and young children, doctors may take a bone marrow aspirate below the knee from the front of the lower leg bone (called the tibia). A bone marrow biopsy is always taken from the hip bone.

You will lie on one side or on your stomach on a table or bed. The healthcare team may give you medicine to help you relax. They will use an antiseptic solution to clean the skin in the area where the needle will go in and will place a sterile drape around the area, leaving only a small area of skin showing. They will inject a local anesthetic to numb the area where the needle will go into the skin. You may feel some burning or stinging when the anesthetic is injected. Both the aspiration and biopsy procedures are usually done at the same time. A bone marrow aspiration is usually done first, followed by a bone marrow biopsy.

For a bone marrow aspiration, the doctor or nurse practitioner passes a special needle through the skin and bone into the bone marrow. A syringe is then attached to the special needle and a small amount of bone marrow fluid, which looks like blood, is withdrawn. You may feel pain, but it lasts only a few seconds. Sometimes, several aspirations are taken for different tests.

For a bone marrow biopsy, the doctor or nurse practitioner uses a special needle that twists into the bone. This needle removes a small core of solid bone tissue and marrow. You will feel pressure when the biopsy needle passes into the bone and as the needle and biopsy are being removed from the bone.

The doctor or nurse practitioner removes the needle after collecting the sample. Samples are sent to a lab to be examined under a microscope.

The doctor or nurse will clean the area with alcohol, put a bandage over it and apply pressure to the area for a few minutes to stop the bleeding. You will stay lying down for 20–30 minutes after the biopsy. When the bleeding has stopped and you can leave the clinic or hospital, you may go back to your normal activities.

Side effects

Bone marrow aspiration and biopsy usually don’t cause serious problems. Some people may have the following side effects where the needle was inserted:

  • tenderness or pain
  • bleeding or bruising
  • redness or swelling

What the results mean

Bone marrow aspiration and biopsy can show if:

  • you have certain types of cancer, such as leukemia, multiple myeloma, non-Hodgkin lymphoma (NHL) or Hodgkin lymphoma
  • cancer has spread to the bone marrow
  • you have anemia or a blood disorder

These procedures can also tell the healthcare team whether bacteria or fungi have caused an infection in the bone marrow.

What happens if a change or abnormality is found

Your doctor will decide if you need more tests, procedures, follow-up care or additional treatments.

Special considerations for children

Preparing children before a test or procedure can lower anxiety, increase cooperation and help them develop coping skills. Preparation includes explaining to children what will happen during the test, including what they will see, feel and hear.

Most children will be given a general anesthetic before bone marrow aspiration and biopsy. It is given through an intravenous (IV) line placed in a vein in the child’s hand.

Sometimes an older child can have a local anesthetic and sedation. The healthcare team will put a numbing cream on the biopsy area before the test is done.

The preparation for bone marrow aspiration and biopsy depends on the age and experience of the child. Find out more age-specific information on how to prepare a child for tests and procedures.

Expert review and references

Medical disclaimer

The information that the Canadian Cancer Society provides does not replace your relationship with your doctor. The information is for your general use, so be sure to talk to a qualified healthcare professional before making medical decisions or if you have questions about your health.

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