Radioiodine-131 (I-131) is used in the treatment of thyroid diseases: hyperthyroidism and differentiated thyroid cancer (DTC: papillary, follicular, Hurthle cell cancer). Treatment success depends on several factors. The most fundamental factor affecting the success of treatment is the susceptibility to target tissue I-131. In patients with differentiated thyroid cancers following total thyroidectomy, I-131 is given for ablation of residual thyroid tissue and treatment of metastatic disease. Physical and biological characteristics of I-131, uptake and effect mechanisms of the iodine in the thyroid follicular cells, indications and contraindications for I-131 therapy, patient preparation and administration of I-131, follow-up and precautions on possible side effects, and an overview on the clinical studies about I-131 therapy are presented.
Part of the book: Radionuclide Treatments
I-131 metaiodobenzylguanidine (MIBG) is a noradrenaline analogue and acts as an adrenergic neuron blocker. It is commonly used in the radionuclide treatment of neuroectodermal-derived tumors (Stage III–IV neuroblastoma, inoperable pheochromocytoma, paraganglioma and carcinoid tumor, metastatic or recurrent medullary thyroid cancer). These are rare tumors and clinical data about therapeutic options accumulate slowly. I-131 MIBG has a well-known role in the salvage therapy of these tumors; however, recent data suggest that it may also be beneficial to use as the first-line method. Here, we define characteristics of the radiopharmaceutical, mention cautions during administration and discuss clinical applications of I-131 MIBG therapy of the neuroectodermal tumors.
Part of the book: Radionuclide Treatments