The short answer
A bone marrow biopsy removes a small sample of tissue or fluid using a needle, so a pathologist can examine it under a microscope. Some biopsies use a sedative or local anesthesia to help you stay comfortable. Bone marrow samples are often studied further, including cytogenetic analysis and immunophenotyping, especially to help diagnose blood cancers like leukemias or lymphomas.
A biopsy removes a sample of tissue or fluid that a pathologist examines under a microscope.
Bone marrow aspirations use a needle to withdraw the sample, similar to how some other biopsies are done.
Some biopsies use a sedative, which helps you relax and stay still or sleep, or local anesthesia, which numbs a small area.
Bone marrow samples can be examined for cells, and are often studied further with cytogenetic analysis and immunophenotyping.
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The full explanation.
The short version
If your doctor has recommended a bone marrow biopsy, it can help to understand the basic idea before the appointment. A biopsy removes a sample of tissue or fluid that a pathologist examines under a microscope. For a bone marrow biopsy, that sample is taken from your bone marrow using a needle, in a method called a bone marrow aspiration.
Why bone marrow is examined
Bone marrow can be examined for cells, which gives your care team information that other tests cannot. This is especially important for diagnosing blood cancers, such as leukemias and lymphomas, since these conditions affect the cells made in the bone marrow.
Bone marrow samples are often studied further using tests called cytogenetic analysis and immunophenotyping. These tests look closely at the cells in the sample, including their chromosomes and the markers on their surface, to help your doctor understand exactly what is happening and reach a diagnosis.
How the sample is taken
A needle is used to withdraw tissue or fluid for a bone marrow aspiration. This same needle-based approach is also used for some other procedures, such as spinal taps and certain breast, prostate, and liver biopsies, so if you have had one of those before, the general idea will be familiar.
Managing comfort during the procedure
Some biopsies require a sedative, which is medicine that helps you relax and stay still or sleep during the procedure. Others use local anesthesia, which causes loss of feeling in one small area of the body. Which one is used — or whether both are used — depends on your specific procedure and your care team's approach. Ask ahead of time what to expect for your appointment, so you know what kind of comfort measures will be in place.
What happens to your sample
After your sample is collected, it goes to a pathologist, a doctor who specializes in examining tissue and fluid samples under a microscope. The pathologist studies the sample, sometimes alongside cytogenetic analysis and immunophenotyping, and describes what they find in a document called a pathology report. This report is what your doctor will use to explain your results and next steps.
While you wait for results
Waiting for a pathology report can be one of the harder parts of this process emotionally. It can help to ask your care team roughly how long the results usually take and who will go over them with you, so you have a sense of the timeline rather than an open-ended wait.
Questions for your team
Before your biopsy, it is worth asking what kind of comfort measures will be used, what specific tests will be run on your sample, and roughly when you can expect results. Having clear answers ahead of time can make the day of the procedure feel much more manageable.
Words to know
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Common questions
▸What is a bone marrow biopsy?
A bone marrow biopsy is a type of biopsy that removes a sample of tissue or fluid from the bone marrow using a needle, so a pathologist can examine it under a microscope.
▸Does a bone marrow biopsy hurt?
Some biopsies require a sedative, which helps you relax and stay still or sleep, or local anesthesia, which causes loss of feeling in one small area. Ask your care team what will be used for your procedure so you know what to expect.
▸Why do I need a bone marrow biopsy?
Bone marrow can be examined for cells, and cytogenetic analysis and immunophenotyping are often done on bone marrow samples to help diagnose blood cancers such as leukemias and lymphomas.
▸What happens to the sample after it's taken?
A pathologist examines the tissue or fluid sample under a microscope and describes the findings in a pathology report.
▸Are other biopsies done with a needle too?
Yes. A needle is used to withdraw tissue or fluid for bone marrow aspirations, spinal taps, and some breast, prostate, and liver biopsies.
Questions to ask your doctor
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