Genes shape the choice.
Up to four in ten pheochromocytomas and paragangliomas arise from an inherited mutation, and the gene involved changes the plan. Tumors driven by SDHB mutations take up MIBG less, spread more readily and show better on a Dotatate PET/CT, which points toward lutetium-177 Dotatate. Tumors with other mutations, or none, take up MIBG strongly in the majority of cases. A patient whose tumors light up on both scans can receive either treatment, and the team weighs the dose each tumor would receive, the kidney and bone marrow reserve, and the availability of each drug before choosing, since the two treatments have never been compared head to head in a randomized trial.
Carcinoid tumors and medullary thyroid cancer once received MIBG too. Lutetium-177 Dotatate and targeted drugs have largely replaced it there, and the page concentrates on the two main uses.
How is the treatment prepared and given?
Preparation starts weeks before admission.
The treatment
1
Admission and infusion
The patient is admitted to a shielded single room. The MIBG runs into a vein over one to two hours, with blood pressure and heart rate monitored, since the tumor may release hormones as it is treated.
2
Isolation
The room stays closed to visitors for three to five days while the radiation falls. For a child, one parent stays in a shielded area of the room with a radiation badge, trained to care for the child while limiting close contact.
3
Scan and discharge
A whole-body scan before discharge shows where the MIBG went. Counts follow weekly for six weeks. In neuroblastoma the stored stem cells go back if the marrow is slow to recover, a simple drip given in the day unit or on the ward that restores the blood-forming cells within two to three weeks.
Preparation
- Potassium iodide or a similar tablet protects the thyroid, starting a day before and continuing for about two weeks.
- Some medicines block MIBG uptake and are stopped beforehand, including labetalol, some antidepressants, some calcium channel blockers and decongestants. The team reviews every medicine.
- Blood counts, kidney function and, in children, stored stem cells are checked before admission.
- Stay in the shielded area assigned to you, and keep contact with the patient to what care requires.
- Wear gloves for nappies, vomit and bedding in the first days, and follow the staff's instructions for waste.
- Siblings, pregnant relatives and other children do not visit until discharge.
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Results in relapsed or resistant neuroblastoma
| Study |
Patients |
Result |
| Phase II, Journal of Clinical Oncology 2007 |
164, aged 2 to 30 |
Response 36 percent. Survival 49 percent at one year, 29 percent at two |
| Systematic review, European Journal of Cancer 2014 |
1,121 in 30 studies |
Average response 32 percent, range 0 to 75 |
| NANT randomized phase II, Journal of Clinical Oncology 2021 |
105 evaluable |
Response after one course 14 percent with MIBG alone, 32 percent with vorinostat added |
Results in pheochromocytoma and paraganglioma
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Results in advanced pheochromocytoma and paraganglioma
| Study |
Patients |
Result |
| High-specific-activity MIBG, Journal of Nuclear Medicine 2019 |
68 treated |
Blood pressure medicines halved for six months in 25 percent. Partial response or stable disease in 92 percent. Median survival 36.7 months |
| Meta-analysis, Clinical Endocrinology 2014 |
243 in 17 studies |
Partial response 27 percent, stable disease 52 percent. Hormonal response 40 percent partial, 11 percent complete |
Side effects
Nausea in the first days, a fall in blood counts that reaches its lowest point four to six weeks after treatment, and tiredness are the most common. In the neuroblastoma study, severe liver, lung or infection problems were uncommon, 5, 3.6 and 10.9 percent. The thyroid may slow over the years despite protection. Thyroid tests continue for that reason. High cumulative doses carry a small risk of later blood disorders. In paraganglioma, the tumor can release hormones during treatment, and blood pressure is watched closely.
Children need more than a room.
A few days alone in a shielded room is hard for a small child. Play specialists and nurses prepare the child beforehand with pictures of the room, the family brings favorite toys and a tablet, which are wiped and kept, and some centers use video calls to connect the child with siblings at home. Very young children may need a urinary catheter so that radioactive urine does not soak bedding and nappies, and some need light sedation for the infusion. These details are planned with the family before admission.
Days, cost and the trip
Plan ten to fourteen days in Istanbul. That covers the diagnostic scan if not already done, the assessment, three to five days of isolation after the infusion, and the scan before discharge. Weekly blood counts follow at home. Families fly home once the radiation readings allow, with a letter for airport detectors, and keep a short distance from others for the first days at home.
Cost depends on the MIBG dose, which is ordered for each patient, the nights in the shielded room, and for children the stem cell work. A quote should list each part. Your own figure follows the free review of your file.
One coordinator handles your visit. The team works in seven languages, with interpreters for the rest. Ten days before travel, an invitation letter naming the hospital and the physician goes out, and the international patients office books the transfer and an apartment or hotel for the family. Halal, vegetarian and diabetic meals come on request, a prayer room is on site, and a request for a female doctor is passed to the department and met wherever the rota allows. Back home, the coordinator stays reachable on the same WhatsApp number while the blood counts recover.
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A typical treatment stay
| Step |
Timing |
| Diagnostic MIBG scan and assessment |
Days one to three |
| Thyroid protection starts |
The day before the infusion |
| Infusion and isolation |
Three to five days |
| Scan before discharge |
Last day of isolation |
| Blood count checks |
Weekly for six weeks, at home |
Iodine-131 MIBG is an active treatment for neuroblastoma, but its place in the management of neuroblastoma remains unclear. Prospective randomised trials are essential to strengthen the evidence base.
Systematic review, European Journal of Cancer, 2014
I-131 MIBG therapy FAQ
What is I-131 MIBG therapy?
A targeted radiation treatment in which MIBG, a molecule taken up by nerve-cell tumors, carries iodine-131 into neuroblastoma, pheochromocytoma and paraganglioma cells.
How effective is MIBG therapy for neuroblastoma?
In relapsed or resistant disease, response rates average about a third, 36 percent in the largest phase II study. Adding vorinostat raised the response to 32 percent against 14 percent for MIBG alone in a randomized trial.
How effective is it for paraganglioma?
In 68 adults with advanced disease, 92 percent had tumor shrinkage or stable disease and a quarter halved their blood pressure medicines for six months or more.
How long is the hospital stay?
Three to five days in a shielded room after the infusion, and ten to fourteen days in Istanbul in all.
Can a parent stay with a child during isolation?
Yes. One parent stays in a shielded area of the room, wears a radiation badge and is trained by the staff.
Can my family come with me?
Yes. The international patients office arranges an apartment or hotel near the hospital for the family.
References
- Matthay KK, Yanik G, Messina J, et al. Phase II study on the effect of disease sites, age, and prior therapy on response to iodine-131-metaiodobenzylguanidine therapy in refractory neuroblastoma. Journal of Clinical Oncology. 2007;25(9):1054-1060.
- Wilson JS, Gains JE, Moroz V, Wheatley K, Gaze MN. A systematic review of 131I-meta iodobenzylguanidine molecular radiotherapy for neuroblastoma. European Journal of Cancer. 2014;50(4):801-815.
- DuBois SG, Granger MM, Groshen S, et al. Randomized Phase II Trial of MIBG Versus MIBG, Vincristine, and Irinotecan Versus MIBG and Vorinostat for Patients With Relapsed or Refractory Neuroblastoma: A Report From NANT Consortium. Journal of Clinical Oncology. 2021;39(31):3506-3514.
- Pryma DA, Chin BB, Noto RB, et al. Efficacy and Safety of High-Specific-Activity 131I-MIBG Therapy in Patients with Advanced Pheochromocytoma or Paraganglioma. Journal of Nuclear Medicine. 2019;60(5):623-630.
- van Hulsteijn LT, Niemeijer ND, Dekkers OM, Corssmit EP. 131I-MIBG therapy for malignant paraganglioma and phaeochromocytoma: systematic review and meta-analysis. Clinical Endocrinology. 2014;80(4):487-501.
