Metaiodobenzylguanidine (MIBG) is a substance that is taken up specifically by neuroblastoma, pheochromocytoma, or paraganglioma tumor cells. MIBG can be combined together with radioactive iodine (131I) in the laboratory to form the radioactive compound 131I-MIBG. The 131I-MIBG compound concentrates more in cancer cells than in normal cells, and may therefore deliver more radiation directly to cancer cells while sparing normal organs.
Arsenic trioxide is a drug that has been shown to kill neuroblastoma cells in the laboratory. It has been used safely in children and adults with various cancers. In laboratory studies, arsenic trioxide was more effective against cancer cells when given with radioactivity delivered specifically to the tumor.
The purpose of this research study is to assess the safety and effectiveness of the combination of 131I-MIBG and arsenic trioxide in patients with neuroblastoma, malignant pheochromocytoma, or malignant paraganglioma that has returned or is resistant to standard treatments.