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I-131 metaiodobenzylguanidine therapy is a significant treatment option for pheochromocytoma and paraganglioma.

AIM
Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumours of chromaffin cells. Several modalities are currently available to treat patients with PPGL. These treatment modalities include surgery, chemotherapy, molecular targeted therapy and radiopharmaceuticals.


METHODS
I-131 metaiodobenzylguanidine (mIBG), a classic radiopharmaceutical, can be taken up through specific receptors and sited into many, but not all, PPGL cells.


RESULTS
Many studies have investigated the efficacy and toxicity of I-131 mIBG therapy. These studies reported significant results in terms of objective, hormonal and symptomatic responses as well as tolerable toxicities in patients.


CONCLUSION
This article reviews the reported experiences of patients who underwent I-131 mIBG therapy for PPGL with a focus on functions and deficiencies of the therapy.