Bone marrow aspirate / Trephine biopsy for children

As some cancers can affect the bone marrow, it needs to be checked at the time of diagnosis and during treatment. This is done by taking a sample of bone marrow or bone using a needle. 

When a sample of semi-liquid bone marrow cells is taken, it is called an aspirate. The doctor may also take a tiny piece of bone or solid marrow. This is called a trephine biopsy. A different kind of needle is used to do the trephine biopsy. 

Before the test

Your child will have a general anaesthetic before the test, so they will need to fast (not eat or drink) for a time beforehand.

During the test

Your child will have a needle put into one of their bones (usually the hip) and a small amount of marrow will be taken out (aspirate). Sometimes a sample of bone is taken too (trephine biopsy). 

How long does it take?

About 20-30 minutes.

Does it hurt?

You child will be asleep during the procedure so they won’t feel anything, but they may be a bit sore afterwards. You doctor can recommend a mild painkiller that they can take for a day or two, if needed. If the pain gets worse, tell the hospital. 

After the test

Your child can go home once they have recovered from the anaesthetic. The samples will be sent to be examined in a laboratory.

Are there risks / side-effects?

• Pain: Your child may feel some pain or discomfort in the area for a day or two after the biopsy.
• Bruising: Your child may get a dark patch under their skin, caused by bleeding under the skin (haematoma). This will clear up on its own.
• Infection: It’s possible to get an infection where the needle goes in, but it’s rare. If the area gets red or sore or your child has a temperature, let the hospital know.