Tests for neuroblastoma

Ultrasound scans use high frequency sound waves to create a picture of part of the inside of the body. This can help doctors to understand what an unusual lump might be.

The ultrasound scanner has a probe that gives off sound waves. The probe looks a bit like a microphone. The sound waves bounce off the organs inside your child’s body, and the probe picks them up. The probe links to a computer that turns the sound waves into a picture on the screen.

Ultrasound scans aren’t painful, but they can cause some discomfort.

Your child has the test in the hospital x-ray department.

A specialist healthcare professional called a sonographer does the test.

What happens before the ultrasound scan?

The hospital will let you know how to help your child prepare for the test.

For some types of ultrasound, it helps if your child has a full bladder. So your child may be asked to make sure they need to have drunk some water beforehand. For other scans your child might not be allowed to eat or drink for a certain amount of time beforehand.

This type of preparation helps your doctor see their organs more clearly.

Your child lies on the couch next to the ultrasound machine. They might be able to sit up depending on which part of the body is being scanned.

You can use distraction methods to help your child lie or sit still while they are having the scan.

The sonographer will also ask you to loosen or remove their clothes so they can get to area that needs scanning.

How does your child have an ultrasound scan?

The sonographer first spreads some gel on the area of skin over where they want to scan. Sometimes the gel can be cold. They gently then place the probe on your child’s skin and slide it over the gel. They might feel a little pressure while they are scanning the area.

After the ultrasound scan

Your child can usually eat, drink and play as normal after an ultrasound scan.

Neuroblastoma is at type of ​neuroendocrine tumour (NET)​. Neuroblastoma cells have receptors on their surface. These attract and take up (absorb) a substance called mIBG. mIBG stands for metaiodobenzylguanidine. This travels around and attaches to these receptors of the neuroblastoma cells. An mIBG scan looks for this absorption in the body so it helps doctors diagnose neuroblastoma.

How does your child have an mIBG scan?

To help show up the mIBG on the scan doctors attach a very small amount of radioactive iodine. They then inject this into the bloodstream. Doctors call this injection the tracer. The neuroblastoma cells pick up the mIBG. Then the radioactive iodine attached to it shows up on the scan.

Having a radioactive injection might sound scary. But, the dose of radioactivity is as low as possible to provide good pictures. An mIBG scan is a safe test. Your doctor will go through the risks and benefits of your child having the test with you.

This test is done over 2 days. On the first day, your child has the injection of the tracer. On the second day, your child has more detailed pictures taken during a second scan. Distraction can help older children keep still for the scan. Younger children often need a sedative to make them sleepy and help them lie still. Or they might have a general anaesthetic for the test. This test can take at least 90 minutes. 

Some of the tracer can be absorbed by the ​thyroid​ gland. To help prevent this your child has some potassium iodide medicine to take. They usually have this medicine:

• the day before the scan

• on the day

• the day after their scan

After their mIBG scan

The radioactive tracer comes out of your child’s body over the next few days in their pee and poo. Your child’s team let you know the best ways to look after your child over the next few days.

Let your child’s team know if you are, or think you could be, pregnant. The amount of radioactive tracer is small but pregnant women should avoid close contact with anyone having this type of scan. If you are pregnant you might need someone else to care for your child for the short time during and after them having an mIBG scan.

A bone scan shows up changes or abnormalities in the bones. Your child might have this test to help doctors find out if the neuroblastoma has spread to the bone. 

How does your child have a bone scan?

First, a technician gives your child an injection of a radioactive liquid called a radionuclide. They inject it through a small tube (cannula) into their bloodstream. It’s a very small amount and doesn’t harm your child. The injection might make them feel hot and flushed for a minute or two but this is normal.

Your child waits for up to 4 hours while the radioactive liquid travels through the blood and collects in the bones. They can play as normal during this time. It’s important that they have lots to drink, so that they can have a pee just before the scan starts.

They then lie down on an x-ray couch and need to keep very still. Some children have a sedative drug to make sure they are sleepy and can lie still. Other children have sandbags around them to help keep them in the same position for the scan.

A camera moves around your child. It takes pictures of the bones in their whole body.

The liquid tends to collect more in areas where the bone is breaking down and repairing itself. These areas of activity (called hot spots) show up on the scan. They look darker than other areas of bone.

After their scan

Your child has a small amount of radiation in their body after the scan. The exposure to radiation is similar to the amount that we get from the environment in 2 years. It can increase their risk of developing cancer in the future by an extremely small amount. Talk to your doctor if this worries you.

Your child’s body gets rid of the radionuclide through the urine, usually within 24 hours. And your child’s radiographer or doctor will explain all the risks and benefits to you before you consent to the scan.

Your child’s nurse will look after them closely when they return and take regular measurements. This is so the team can be sure they have recovered and are awake enough from the sedation or anaesthetic. The nurses usually check that your child has had:

• something to drink

• something to eat or some milk

• a pee

Your child can usually go home the same day, unless they are staying in hospital for other tests.

Your child has this test to check whether there are neuroblastoma cells in the bone marrow. Bone marrow is spongy tissue and fluid that is inside your bones. It makes your blood cells.

How does your child have a bone marrow test?

A doctor or specialist nurse removes a sample of bone marrow cells (called a bone marrow aspirate). Or an area of bone marrow in one piece (called a trephine). Your child might have both tests at the same time. Doctors can then look at the cells or tissue under a microscope.

Doctors might take a sample from both hips, when they are testing the bone marrow for neuroblastoma cells.

Or, if your child is very young, they might have the sample taken from a bone in their leg.

Most children and young people have this test under general anaesthetic. Or they might have a medicine to make them feel sleepy and relaxed (sedative). This helps them to lie still on the couch while they have the test.

Some older children might have gas and air (Entonox) instead of sedation to help them relax.

After the bone marrow test

After their test your child’s nurse will look after them closely when they return and take regular measurements such as their:

• heart rate

• breathing rate

• blood pressure

• oxygen levels

• temperature

This is so they can be sure they have recovered and are awake enough from the sedation or anaesthetic. The nurses also usually check that your child has:

• had something to drink

• had something to eat or some milk

• had a pee

• a clean and dry dressing over the site of the test

A bone marrow biopsy is a safe test. Your child’s doctor or nurse talks with you about any possible problems they might have after it. They give you a phone number to call if you have any problems after, if in doubt, give the number a call.

It’s likely your child can go home the same day, unless they are staying in hospital for other tests.

Your child’s doctor takes a sample of an abnormal area seen on a scan. This is called a biopsy. A specialist doctor called a pathologist looks at the cells down a microscope to find out exactly what is causing the lump.

How does your child have a biopsy?

Your child is likely to have a general anaesthetic for this test. This means they are asleep and can’t feel anything during the test.

An experienced doctor takes a small sample of cells using a needle. The doctor uses a scan to help them choose the best place to biopsy.

After their biopsy

The nurses usually check that your child has:

• had something to drink

• had something to eat or some milk

• had a pee

• a clean and dry dressing over the site of the test

Children might go home the same day. Or they might stay in hospital overnight for other tests.

A biopsy is a safe test. Your child’s doctor goes through the risks and benefits with you. The most common risks are bleeding from the site or infection. Your team gives you a telephone number to call if you have any problems at home. If in doubt, give them a call.

Doctors can use urine tests to help diagnose neuroblastoma. Neuroblastoma cells often make chemical messengers called catecholamines (cat - a - coal - ay - means). Our bodies normally make these in a controlled way when we need them. When the body breaks down catecholamines, they normally pass out of the body in urine. Neuroblastoma tumours often produce catecholamines in large amounts. So measuring the amount of them in the urine can help your doctor diagnose neuroblastoma. 

There are different types. The ones that doctors test for to diagnose neuroblastoma are HMA (homovanillic acid) and VMA (vanillylmandelic acid).

How does your child have a urine test?

Your doctor asks your child to give a urine sample into a pot if they are old enough or able to. There are different ways to collect urine from younger children, or from children who might find this difficult. These include:

• using a urine collection bag – these are designed with a sticky edge so you can attach them easily. They peel off when your child has had a pee. The pee can be poured into the sample container

• putting a layer of sterile cotton wool, urine collection pad or gauze inside a fresh nappy – you can use a syringe to draw up the sample when your child has passed urine

• taking a clean sample from your child’s catheter, if they have one – the nurses at the hospital should be able to do this for you

After the urine test

Your child can usually eat, drink and play as normal after giving a urine sample.