What you need to know

If your child has neuroblastoma or other neuroendocrine cancer that has not responded to treatment, I-131 MIBG therapy may be the next step.

I-131 MIBG is a medicine made by a specialized pharmacist. The drug contains a form of radioactive iodine called I-131 and metaiodobenzylguanidine (MIBG).

MIBG is very similar to a neurotransmitter chemical absorbed by neuroendocrine cells. When I-131 MIBG builds up within a tumor, it gives off radiation that destroys the cancer cells.

About the therapy

What is I-131 MIBG treatment?

Your child receives I-131 MIBG therapy by infusion. The medicine travels through your child’s bloodstream to the tumor.

Your child’s body removes the radiation not absorbed by the cancer cells through their urine. It takes two to five days for your child’s body to achieve safe radiation levels after they’ve received a dose of I-131 MIBG. The exact amount of time depends on the dose of I-131 MIBG given, the extent of the tumor being treated and your child’s kidney function.

The I-131 MIBG treatment can be very effective at destroying hard-to-treat neuroendocrine cancers. Your child will take medicines to protect other parts of the body from the radiation. Your child might experience low blood counts and thyroid problems after treatment.

Clinical trials using I-131 MIBG treatment

We have several clinical trials available that use I-131 MIBG to treat children with neuroblastoma.  These are briefly summarized below:

This study administers high doses of I-131 MIBG to children with relapsed or refractory neuroblastoma. Up to three treatments may be given.

This trial utilizes lower doses of I-131 MIBG, combined with immunotherapy, to treat children with relapsed or refractory neuroblastoma. The immunotherapy consists of an antibody that attaches to neuroblastoma cells and a drug that helps your child’s immune system work better.

A phase 2 trial that combines I-131 MIBG with vorinostat to treat children with relapsed or refractory neuroblastoma. This combination resulted in a better response rate than I-131 MIBG given alone, in a prior study.


What to expect

It only takes a short time to give your child the I-131 MIBG treatment. You will spend more time preparing for the hospital stay.

Before your child gets a I-131 MIBG treatment, we take many safety precautions. We protect you and your child from the radioactive iodine with a specialized treatment room and lead shields.

Our radiation safety team and nurses will train you to care your child. We will also teach you how to keep yourself safe from radiation during and after the hospital stay. Our child life specialists will help you create plans to keep your child engaged and comfortable throughout their hospital stay.

Your child’s care team monitors your child during the I-131 MIBG infusion. The treatment takes about 90 minutes and is not painful. Children usually do not feel sick. 

For most children, the hardest part of I-131 MIBG treatment is staying away from others after the radiation is administered. It typically takes two to five days for the majority of the radiation to leave the body, at which time your child can safely return home.

Things to consider

Your child needs toys and activities to stay busy in the days after treatment. Pack items that can be thrown away after treatment, such as:

  • Coloring books and crayons

  • Card games 

  • Inexpensive toys 

The room in which your child will stay has an audiovisual system so they can watch television and movies. We can also provide an electronic tablet that your child can use during their stay. Remember to bring any guides or information you received about your child’s care and safety.

Your child stays in a special hospital room built to contain radiation. The room includes:

  • A lead box at the foot of the bed to shield the urine bag, which collects radioactive urine from your child 

  • A urine pump and system to remove radioactive urine from the room

  • A motorized lead door

  • A large mobile lead shield between your child’s bed and the door

  • Lead in the walls, floor and doors to keep radiation from extending past the room

  • Lead shields to protect hospital staff and your family 

  • Special waste containers 

  • Surfaces (floors, bedrails, telephone) covered with plastic

  • Closed-circuit TV for communication 

  • Television for entertainment

  • Video gaming system for your child’s use

After your child settles into the hospital room, their care team begins preparing for the infusion.

Your child might need a Foley catheter to collect urine. This is a small, flexible tube that a nurse places into the bladder. Although this is a simple and fast procedure, we typically have the catheter inserted while your child is heavily sedated to ensure there is minimal discomfort. 

When your child’s care team is ready to begin treatment, a nuclear medicine technologist brings a syringe of I-131 MIBG into the room on a cart with a lead shield.

The doctor gives the I-131 MIBG to your child through an IV. The infusion takes about 90 minutes. You and the care team monitor your child during and after the infusion.

Our program is designed to minimize contact with your child after treatment, while still keeping them happy and safe. This reduces radiation exposure to you and health care providers. 

You can expect your child to be in the hospital for two to five days. During this time:

  • Your child’s body expels radiation through their urine.

  • Your child can eat, play games, read, draw, etc.

  • You help care for your child by providing comfort and performing tasks like bringing in meals, helping with toileting needs, etc.  You will be taught how to safely provide care while inside the I-131 MIBG room.

  • You will spend much of your time in a sleep room located right next to the 1-131 MIBG room.

  • From the sleep room you can talk with, and see your child, utilizing our closed-circuit AV system.

  • Your child can leave the hospital when the radiation is at a safe level.

Once you return home, you need to continue to take precautions to protect others from low levels of radiation. This should continue for a few weeks or until your child’s doctor says your child’s radiation levels are safe. Our radiation safety team will provide specific guidelines for you before your child is discharged from the hospital.

The care team monitors your child’s health and blood counts for several weeks after treatment. Scans are usually done around six weeks after the I-131 MIBG infusion to assess your child's response to the treatment.

If your child’s doctor recommends I-131 MIBG therapy, you will meet with the care team to discuss the treatment. You can ask questions of the radiotherapy doctor, nurse practitioner, social worker and other team members. Together they will:

  • Review your child’s cancer history

  • Talk about radiation safety

  • Talk about the treatment

  • Discuss a plan to keep your child comfortable and engaged during their hospital stay

  • Obtain consent to proceed with I-131 MIBG therapy

Meet our team

A caring team for you and your child

Our providers


MIBG treatment locations

We provide specialized MIBG treatments at American Family Children’s Hospital in Madison, Wis.

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UW Health Kids
Our pediatric experts have served the special needs of children for more than 100 years. We focus on each child’s unique needs and offer social and emotional support to help you and your child face even the most complex condition. Our long history includes the creation of medical advances that save lives around the world. Together, we get your child back to health and enjoying being a kid.

Patient and support services

You’re never alone

When your child needs hospitalization, they will be admitted to American Family Children's Hospital in Madison, Wis.

Child life specialists help your child and family cope with any fears and anxieties. The American Family Children's Hospital patient and family visitor guide features information about:

  • Hero beads

  • Hospital school

  • Positive Image Center

  • Restoring Hope Transplant House (for blood and bone marrow transplant)

  • Spiritual care services

  • Tyler's Place (sibling child care)

Additional resources

Pediatric cancer services

With our expertise comes compassion. Our team considers you and your child part of our family. We will be by your side every step of the way. From diagnosis through treatment and into adulthood, we will care for your child as if they are our own.

Learn more

Pediatric cancer services

With our expertise comes compassion. Our team considers you and your child part of our family. We will be by your side every step of the way. From diagnosis through treatment and into adulthood, we will care for your child as if they are our own.

Learn more