Aneurysmal bone cyst

Treatment in Interventional Radiology

What is an Aneurysmal Bone Cyst (ABC)?

An aneurysmal bone cyst (ABC) is a benign bone tumor.  Benign means it is not cancer.  The cyst is a liquid or blood-filled sac that expands the bone.  It can make the bone very thin and easy to break. These are common during the teenage years.  They can happen in any bone.  They do not spread to other parts of the body, but may come back after treatment.  The cysts do not go away on their own. If the cyst is in certain areas of the body, like the skull or spine, it can be dangerous.

What causes an Aneurysmal Bone Cyst?

The cause of these cysts is not known. There is nothing that you or your child could have done to prevent them.

What are the symptoms?

Common symptoms are pain, swelling, bone deformity or broken bone (fracture).  

How is it diagnosed?

Aneurysmal bone cysts are diagnosed by X-ray, MRI or CT scan.  MRI is most often used to look at the bone cyst and areas around it.  A biopsy may also be done during the first treatment to confirm diagnosis. A small amount of the bone cyst is taken to be looked at under a microscope. 

How is it treated?

One treatment for these bone cysts is Sclerotherapy.  It is a treatment where a doctor puts medicine into the cyst to help it shrink.  It is done in Interventional Radiology by an interventional radiologist. 

1. This procedure takes 1 to 2 hours and is always done while your child has general anesthesia (sleeping).  
2. The Interventional Radiologist uses an X-ray machine and CT imaging to guide a small needle into the cyst.  
3. Next, they inject tiny amounts of medicine, called Doxycycline.  The medicine scars the walls inside of the cyst.  
4. Over time the scar tissue replaces the liquid or blood within the cyst.  The scar tissue hardens into bone.  This heals the cyst.
5. Your child will go home on the same day, after they recover from the procedure.  Your child’s doctor will discuss any activity limits with you.

How do we know that treatment is working?

Your child will have an MRI every 3 to 5 months to check treatment progress and find out if more injections are needed.  Your child may need more than 1 injection for complete treatment.  

What are some of the risks?

• Your child may have pain at the treated site for a few days after the procedure.  
• Blood vessels, muscles or nerves around the area being treated may be affected.  This could be temporary or permanent.
• Infection can develop at the treated area.  This is rare.

Can the Aneurysmal Bone Cyst come back?

Yes, there is chance that it could come back. We will follow your child with tests 6 months and one year after the last treatment.  After that, your child will be checked each year for the next 2 years.  We will look for regrowth.