Test Overview

A bone marrow biopsy removes a small amount of bone and a small amount of fluid and cells from inside the bone (bone marrow). A bone marrow aspiration removes only the marrow. They are often done to find the reason for many blood disorders and may be used to find out if cancer or infection has spread to the bone marrow.

• Bone marrow aspiration removes a small amount of bone marrow fluid and cells through a needle put into a bone. The bone marrow fluid and cells are checked for problems with any of the blood cells made in the bone marrow. Cells can be checked for chromosome problems. Cultures can also be done to look for infection.
• A bone marrow biopsy removes bone with the marrow inside to look at under a microscope. The biopsy of bone marrow is done first, and taking fluid (aspiration) is often done after the biopsy.

A bone marrow aspiration can also be done to collect bone marrow for medical procedures, such as stem cell transplantation or chromosomal analysis. For a stem cell transplant, bone marrow aspiration will be done at several places on the body (generally from the back of the pelvic bone) to remove enough bone marrow cells for the transplant to work.

Why It Is Done

A bone marrow aspiration, biopsy, or both are done to:

• Look for the cause of problems with red blood cells, white blood cells, or platelets in people who have conditions such as thrombocytopenia, anemia, or an abnormal white blood cell count.
• Find blood disorders, such as leukemia, certain anemias, or problems that affect the bone marrow, such as multiple myeloma or polycythemia vera.
• Check to see if a known cancer, such as Hodgkin's lymphoma or non-Hodgkin's lymphoma, has spread to the bone marrow. This is part of what is called staging. It is done to find out if the cancer has spread and how much it has spread. This helps plan cancer treatment. Staging can be done for other cancers, such as prostate, breast, or lung cancer that may have spread to the bone.
• Find infections or tumors that may start in or spread to the bone marrow. If you have an infection, a culture and sensitivity test of the bone marrow sample may be used to find out which antibiotics will work best to treat the infection.
• Find the best treatment for a bone marrow problem. Once treatment has been started, a bone marrow aspiration and biopsy may be done to see if the leukemia cells are gone, which means the treatment is working.
• Collect a sample of bone marrow for medical procedures, such as stem cell transplantation or chromosomal analysis.

How To Prepare

You will be asked to sign a consent form. Talk to your doctor about any concerns you have about the need for the aspiration or biopsy, its risks, how it will be done, or what the results may mean. To help you understand the importance of the biopsy, fill out the medical test information form(What is a PDF document?).

Tell your doctor if you:

• Are taking any medicines.
• Are allergic to any medicine, including anesthetics.
• Have any bleeding problems or take blood-thinners, such as aspirin, heparin, or warfarin (Coumadin).
• Are or might be pregnant.

Arrange for someone to drive you home after the biopsy because you may be given a medicine (sedative) to help you relax.

How It Is Done

A bone marrow aspiration or biopsy is usually done by a hematologist, medical oncologist, internist, or pathologist, or by a specially trained technologist. A laboratory technologist may also help get the sample. This biopsy may be done in your doctor's office or in a hospital.

You will need to take off all or most of your clothes, depending on what part of the body the biopsy or aspiration is taken from. You will be given a gown to use during the biopsy

Blood samples from a vein in your arm may be taken before the bone marrow biopsy. In rare cases, you may be given a blood product (clotting factor or platelets) into a vein (IV) in your arm to prevent bleeding after the biopsy.

Adults usually have a sample of bone marrow fluid taken from the back of the pelvic bone. In rare cases, a fluid sample is removed from the breastbone (sternum) or from the front of the pelvic bone. Babies and young children may have the sample taken from the front of the lower leg bone, just below the knee. A bone marrow biopsy is only taken from the pelvic bone.

You may be given a sedative to help you relax. You will lie either on your side or facedown, on your belly, for the biopsy. It is important that you lie still in that position during the biopsy. See illustrations of bone marrow aspiration and biopsy in a side-lying position or a facedown position.

The skin over the aspiration site will be cleaned with a special solution and a medicine (local anesthetic) will be used to numb the area. Then the aspiration needle will be put through your skin and into your bone to reach the bone marrow. You need to lie very still while the sample is taken. The needle is then taken out. More than one sample may be needed, possibly from more than one place on your body, such as from both sides of the pelvic bone. This is more likely to happen if the biopsy is being done to stage a condition, such as lymphoma.

A bone marrow biopsy uses a special tool that twists into the bone. It is normal to feel pressure at the site and hear a crunching sound as the tool twists into the bone.

After the samples have been taken, pressure is put on the site to stop any bleeding. A bandage is put on the area.

Each biopsy takes about 20 minutes. After the biopsy, you will remain lying down for 10 to 15 minutes. If the bleeding has stopped, you may do your normal activities. If you have been given a sedative, you may need several hours to rest. If you have an aspiration and biopsy from several places on your body, you may be given pain medicines to take at home or you may need to stay in the hospital overnight.

How It Feels

You may feel a sharp sting and burn when the anesthetic numbs your skin over the aspiration or biopsy site. You may hear a crunching sound and feel pressure and some pain when the needle enters the bone. The pain usually lasts for only a few seconds. During an aspiration, you may feel a quick, shooting pain down your leg as the sample is taken. This pain stops as soon as the sample is removed.

The biopsy site may feel stiff or sore for 1 or 2 days after the biopsy. You may have a bruise on the site.

Risks

Serious problems from a bone marrow aspiration or biopsy are not common. Problems may include:

• Bleeding from the biopsy site. People with bleeding problems have a higher chance for this. If you have bleeding problems, pressure will be put on the biopsy site for at least 10 minutes after the biopsy. In rare cases, you may be given a blood product (clotting factor or platelets) in a vein in your arm before the biopsy to prevent bleeding after the biopsy.
• Infection of skin or the bone (osteomyelitis) at the biopsy site.
• Injury to your heart, a lung, or a major blood vessel if the sample is taken from the breastbone (sternum). This complication is very rare. Samples are not often taken from the breastbone, so most people do not have to worry about this risk.

After the biopsy

You will lie down for 10 to 15 minutes after the biopsy so the site can be checked for bleeding. Your bandage can be taken off after 1 hour. If you had a sedative, you will need someone to drive you home after the biopsy.

You may feel sore at the biopsy site for several days. Ice packs to the site, walking, and pain medicine, such as acetaminophen (Tylenol), can be used to help you feel better.

Call your doctor immediately if you have:

• More tenderness, pain, redness, or swelling at the biopsy site.
• A fever.
• Bleeding or drainage, such as pus, from the biopsy site. If you are bleeding, put pressure on the site and call your doctor.

Results

A bone marrow aspiration and biopsy removes a small amount of bone and a small amount of fluid and cells from inside the bone (bone marrow). It is often done to find the reason for many blood disorders and may be used to find out if cancer or infection has spread to the bone marrow.

Biopsy results are ready in 1 to 3 days. The bone is put into a solution that breaks down its calcium before it is stained. The bone marrow sample is often treated with special dyes (stains) to see any changes in the blood cells more clearly.

What Affects the Test

Reasons you may not be able to have the test or why the results may not be helpful include:

• Having a recent blood transfusion or treatment with medicines that have iron in them.
• Having had radiation treatment in the past to the site where the bone marrow sample is removed. Fewer bone marrow cells or fibrous (scar) tissue may be seen.
• Being obese. Taking a bone marrow sample from the pelvic bone of an obese person may be hard. It may be easier to use the front of the hipbone (anterior iliac crest) or the breastbone (sternum).

Sometimes not enough bone marrow fluid is collected in a bone marrow aspiration. This is called a dry tap. If this happens, a biopsy to obtain bone marrow tissue is usually done.

What To Think About

• If you have an infection, a culture and sensitivity test of the bone marrow sample can be done. If the infection is caused by a bacteria or fungus, the sensitivity test will show which antibiotics will work best to treat the infection.
• Normal bone marrow in one site does not mean that all sites in the body are normal.

References

Other Works Consulted

• Fischbach FT, Dunning MB III, eds. (2004). Manual of Laboratory and Diagnostic Tests, 7th ed. Philadelphia: Lippincott Williams and Wilkins.

• Pagana KD, Pagana TJ (2006). Mosby’s Manual of Diagnostic and Laboratory Tests, 3rd ed. St. Louis: Mosby.

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