What Is MIBG?

MIBG (meta-iodobenzylguanidine) is a molecule that doctors combine with low-dose radioactive iodine to look for neuroblastoma.

After it’s injected into a patient, the MIBG is absorbed by neuroblastoma cells. Then, the patient lies on a table while a special camera or scanner moves over their body and takes pictures. The radioactive iodine will make the cancer cells show up on the scan.

MIBG given with higher-dose radioactive iodine can treat neuroblastoma. It is absorbed by neuroblastoma cells and is radioactive enough to kill them. Kids usually do well with this treatment because it doesn’t cause as many side effects as other cancer treatments and specifically attacks neuroblastoma cells.

Who Can Get MIBG Treatment?

The health care team will explain the risks and benefits of MIBG treatment. It is offered to patients with high-risk neuroblastoma that hasn’t responded well to early treatments and has come back. Researchers are studying whether MIBG might be helpful as one of the first treatments for high-risk neuroblastoma. If the health care team thinks MIBG therapy is right for a child, they and the parents will work together on a treatment plan.

MIBG causes fewer problems in nearby healthy cells because only tumor cells absorb it. It does, though, affect the bone marrow (which makes blood cells). So patients need an IV infusion of their own bone marrows cells (stem cells) a few weeks after MIBG therapy. These cells are collected before treatment.

The treatment’s timing needs careful planning. There are important things to consider. After MIBG treatment, radiation can spread from the child to other people for several days. Radiation also can come out in pee, poop, sweat, and spit during this time. The radiation decreases each day after the MIBG is given. A child getting MIBG treatment usually spends about 4 to 5 days in the hospital. This gives the radiation time to reach a safe level before the child goes home.

Parents are trained in advance to safely care for their child during the hospital stay and at home.

What Happens During MIBG Treatment?

MIBG goes into a child’s vein through an IV or central line. The MIBG runs into the body in under 2 hours and does not hurt. Then the child will then stay in the hospital for a few days and be watched closely.

Because MIBG is radioactive, safety guidelines will keep your child and others safe. These include:

• A special room. Kids get MIBG treatment in a special room made with lead and concrete walls. No one outside the room is exposed to radiation.
• A urine catheter. Your child will have a catheter placed into their bladder before treatment. This lets the care team safely collect and get rid of radioactive urine (pee).
• Iodine medicine. Your child will get medicine to help protect the thyroid gland during and after treatment. The thyroid is very sensitive to radiation.

Can I Stay With My Child During MIBG Treatment?

MIBG treatment is radioactive, so parents must limit their exposure. Despite having limited time with their child, there are many creative ways to help kids feel connected. The health care team will review these and the time limits with each family. The room where a child gets MIBG has a parent room attached to it to let parents be nearby but stay safe.

Parents can see and talk with their child using video and audio connections between the two rooms. They can wear protective gear for quick visits to the child’s room. A pregnant parent can’t be with their child until the radioactivity clears.

Are There Any Side Effects From MIBG Treatment?

Most children don’t feel sick during MIBG treatment and tolerate it well. But side effects can include:

• high blood pressure or low blood pressure
• nausea
• feeling tired
• low blood counts for weeks after treatment, including:
  • too few red blood cells (anemia)
  • too few infection-fighting cells in the blood (leukopenia)
  • too few blood clotting cells (platelets) (thrombocytopenia)

A few weeks after MIBG therapy, the child gets the infusion of bone marrow cells that were collected before treatment.

How Can Parents Help?

The care team will show you how to support your child while limiting your exposure to radiation during and after treatment. They can also suggest age-appropriate ways to talk about the treatment with your child. The medicine itself doesn’t take long to go in, but kids need to spend a lot of time alone for several days. This can be hard. Kids often feel bored, but the hospital can provide toys and activities. Movies and video games can help keep kids entertained. Child life specialists will have other ideas to keep your child occupied.

The health care team will ask you to limit items brought from home because things like toys, books, and clothing can get contaminated with radiation. They’ll need to be thrown out or tested after treatment to make sure they’re safe to take home.

At home, the radiation coming from your child will be lower but not gone. Parents still must follow the care team’s instructions for staying safe around it for about another week. The care team will talk with you about where your child should sleep and go to the bathroom, and who can be near your child.

During and after treatment, it can help to find a support group for parents whose kids are coping with cancer. There are groups specifically for parents of children with neuroblastoma. Ask the care team for recommendations. You also can find support and more information online at:

• American Cancer Society
• The Children's Neuroblastoma Cancer Foundation