A Study Evaluating Ultratrace Iobenguane I131 in Patients With Malignant Relapsed/Refractory Pheochromocytoma/Paraganglioma

Inclusion Criteria: * Be at least 12 years of age * Have a documented (medical record) diagnosis of either pheochromocytoma or paraganglioma * Be ineligible for curative surgery for pheochromocytoma * Have failed a prior therapy for pheochromocytoma/paraganglioma or are not candidates for chemotherapy or other curative therapies * Be on stable antihypertensive medication for pheochromocytoma-related hypertension for at least 30 days * Have at least one tumor site by CT or MR or iobenguane I 131 scan * Have an expected survival of at least 6 months * Subjects must agree to use an acceptable form of birth control (abstinence, IUD, oral contraception, barrier and spermicide or hormonal implant) during this study and for 6 months following Therapeutic Doses of Ultratrace Iobenguane I 131. * Male subjects must agree not to father a child during the period beginning immediately after administration of the first Therapeutic Dose of Ultratrace Iobenguane I 131 during the study and ending six months after administration of the last Therapeutic Dose of Ultratrace Iobenguane I 131. Exclusion Criteria: Subjects will be excluded if any of the following conditions are observed: * \<50% of FDG (if data are available) positive lesions are MIBG avid * Pregnant or nursing females * Active CNS lesions by CT/MR scanning within 3 months of study entry * New York Heart Association class IV heart failure, symptomatic congestive heart failure \[New York Heart Association class IV with another medical disorder\], unstable angina pectoris, cardiac arrhythmia * Received any previous systemic radiotherapy resulting in marrow toxicity within 3 months of study entry or have active malignancy (other than pheochromocytoma/paraganglioma) requiring additional treatment during the active phase or follow up period of the Ultratrace® iobenguane I 131 trial. * Administered prior whole-body radiation therapy * Received external beam radiotherapy to \> 25% of bone marrow * Administered prior chemotherapy within 30 days or have active malignancy (other than pheochromocytoma/ paraganglioma) requiring additional treatment during the active phase or follow up period of the Ultratrace iobenguane I 131 trial. * Karnofsky Performance Status is \< 60 * Platelets \< 80,000/μL * Absolute neutrophil count (ANC) \< 1,200/μL, Total bilirubin \> 1.5 times the upper limit of normal, AST/SGOT or ALT/SGPT \> 2.5 times the upper limit of normal * Diagnosed with AIDS or HIV-positive * Active chronic alcohol abuse, chronic liver disease or hepatitis * Renal dysfunction/impairment * Known allergy to iobenguane that has required medical intervention * Received a therapeutic investigational compound and/or medical device/prior chemotherapy within 30 days before admission into this study * Receiving a medication which inhibits tumor uptake of iobenguane I 131 * Any medical condition or other circumstances (i.e., uncontrolled current illness including but not limited to, ongoing or active infection or psychiatric illness/social situations that would limit compliance with the study requirements. * Any other condition, that in the opinion of the investigator, may compromise the safety or compliance of the subject or would preclude the subject from successful completion of the study