Aspects on radionuclide therapy in malignant pheochromocytomas

Malignant pheochromocytomas/paragangliomas (PCs/PGs) often have distant metastases to the skeleton, liver, and lungs. Radionuclide therapy is valuable for treatment of disseminated tumor disease and could be used as adjuvant therapy after surgery. Patients with local and/or distant metastases of PC/PG should be investigated preoperatively by scintigraphy using both I-123-MIBG and In-111-DTPA-D-Phe(1)-octreotide, to evaluate the possibilities for radionuclide therapy (i.e., a dosimetric estimation of radiation dose to the tumor tissue versus critical normal tissues). Individual patient dose-planning should be performed. For patients in whom positive therapeutic effects are anticipated radionuclide therapy can be applied. Therapy with both I-131-MIBG and (177)Luoctreotate might be favorable in individual patients with lesions visualized by both metaiodobenzylguanidine (MIBG) and octreotide scintigraphy with enhanced therapeutic effects and reduced side effects.