Secondary myelodysplastic syndrome and leukemia following 131I-metaiodobenzylguanidine therapy for relapsed neuroblastoma

Purpose: To describe three patients with secondary leukemia after treatment with I-131-metaiodobenzylguanidine (MIBG) for neuroblastoma. Methods: Of 95 children with refractory neuroblastoma treated with I-131-MIBG at UCSF, 3 have been identified with secondary myelodysplasia/leukemia. The case records and bone marrow results were reviewed, along with a review of the literature. Results: Three patients developed secondary myelodysplasia/leukemia, at 7, 11, and 12 months following (131)-MIBG therapy. Cytogenetic abnormalities included -7q/-5, -7/+2q37, -11 and + 12. Three additional cases were found in literature review of 509 reported patients treated with I-131-MIBG for neuroblastoma. Conclusions: Therapy with I-131-MIBG may contribute to the risk of secondary leukemia in patients who have received intensive chemotherapy, thought the risk of this complication is far lower than the risk of disease progression. Further monitoring for this complication is indicated.