Bone marrow biopsy

The bone marrow is the spongy material found in the centre of larger bones in our bodies. It is the production centre for blood cells, including our red blood cells, white blood cells, and platelets. 

Because myeloma develops in the bone marrow, testing your bone marrow is necessary to confirm your diagnosis. Your bone marrow will also be tested to check how well your treatment is working and can provide specific information that helps your haematologist decide on the best treatment and monitoring for you.  

Bone marrow aspirate and trephine biopsy (BMAT)

To test your bone marrow, you will have a procedure called a bone marrow aspirate and trephine biopsy (BMAT). Most people simply call this procedure a bone marrow biopsy or BMAT. 

A BMAT uses a thin needle to take a small sample of fluid (aspirate) and a small core of bone (trephine) from your bone marrow – usually from your pelvic bone (hip bone). 

The image below shoes where the needle goes for a BMAT.

Your bone marrow samples will be sent to a laboratory for examination and testing. 

The bone marrow biopsy was a bit daunting, but I was given some pain relief, and it was over really quickly.

– Sunita Queensland

How often will I have to have a BMAT procedure?

You will need to have a BMAT as part of the tests done to confirm that you have myeloma.  

How often you will need further BMATs varies from person to person and can depend on:  

• the treatment you are having  
• if you are part of a clinical trial 
• if your doctor thinks that your myeloma has become active again (relapse) 
• if you have oligosecretory or non-secretory myeloma (these types of myeloma cannot be monitored with blood or urine tests, so may need more frequent BMATs) 
• if you have a pre-cursor condition such as monoclonal gammopathy of undetermined significance (MGUS) or smouldering myeloma (SMM) that may have progressed to symptomatic myeloma

Your doctor will only recommend a BMAT when it’s needed to help guide your care. 

Read more about the BMAT procedure in our Understanding the bone marrow biopsy procedure in myeloma infosheet.

What tests are performed on my bone marrow samples?

The tests on your bone marrow aspirate and trephine samples are done to: 

• count how many myeloma cells are present in your bone marrow to confirm a diagnosis, response or relapse using the percentage of plasma cells test  
• look for abnormal proteins on the myeloma cells using a test called immunophenotyping by flow cytometry 
• find DNA changes (mutations) within the myeloma cells through cytogenomic testing  
• measure how many myeloma cells are left in your bone marrow after treatment through a newer type of testing that detects minimal residual disease (MRD). At the moment, MRD testing is mainly used in clinical trials. Ask your treating team if this test might be available to you.  

Read more about these tests in our tests Understanding bone marrow tests in myeloma infosheet.