Targeted radiotherapy with submyeloablative doses of 131I-MIBG is effective for disease palliation in highly refractory neuroblastoma.

Purpose: Treatment of refractory neuroblastoma remains a significant clinical problem. Targeted radiotherapy with 131I-MIBG has demonstrated antitumor activity in heavily pretreated neuroblastoma patients with recurrent disease. Response rates may be correlated with total radionuclide dose per kilogram body weight delivered, but higher dose levels are associated with protracted grade 4 hematologic toxicity.