Role of Iodine-131 MIBG Scanning in the Management of Paediatric Patients with Neuroblastoma

Abstract

Objectives: To evaluate the role of iodine-131 metoiodobenzylguanidine (iodine-131 MIBG) scanning in the management of paediatric patients with neuroblastoma. Subjects and Methods: Forty-three iodine-131 MIBG scans were performed on 26 children, 18 male and 8 female, ranging in age from 8 months to 11 years. Bone scan, computed tomography (CT) images and findings of bone marrow biopsy were compared with the iodine-131 MIBG scan findings. Results: Of the 26 patients, 18 (69%) showed abnormal iodine-131 MIBG avidity and were proven to have a neural crest tumour on histology. The remaining 8 (31%) patients had normal iodine-131 MIBG scans, and histology showed a malignancy other than a neural crest tumour. Iodine-131 MIBG scans showed the primary site in 16 of 17 patients while CT showed 14 primary sites. In follow-up studies, the results were as follows: iodine-131 MIBG showed no evidence of disease in 4 compared with 3 on CT, persistent disease in 2 on iodine-131 MIBG and 4 on CT; recurrence in 1 on iodine-131 MIBG and 0 on CT; MIBG scans detected double the number of bony lesions compared with bone scans. The findings on iodine-131 MIBG scans and bone marrow biopsy were in agreement in 16/18 cases. Patients in whom iodine-131 MIBG scans showed disease resolution had better clinical outcomes. Conclusion: The findings indicate that iodine-131 MIBG scanning is useful for the diagnosis, staging, evaluation of response to therapy and detection of recurrences in patients with neuroblastoma. It exhibited a clear advantage over CT in detecting the primary site and soft issue metastases and was also superior to bone scanning in detecting skeletal metastases. It also reliably demonstrated bone marrow involvement.

Diagnostic Value of Seven Different Imaging Modalities for Patients with Neuroblastic Tumors: A Network Meta-Analysis

“…Nineteen studies [ 14 , 15 , 17 , 18 , 20 - 24 , 26 , 29 , 31 , 36 , 39 – 42 , 44 , 45 ] included at least two tests (imaging methods), and 14 (73.7%) of them were head-to-head studies. Twenty (62.5%) [ 15 , 18 , 20 – 26 , 29 - 31 , 33 , 34 , 36 , 40 - 43 , 45 ] of 32 studies investigated 123 I-MIBG imaging, nine (28.1%) studies [ 14 , 17 , 26 , 27 , 36 , 37 , 39 , 42 , 44 ] focused on 131 I-MIBG, eleven (34.4%) studies [ 16 - 20 , 23 , 24 , 38 – 40 , 42 ] performed 18 F-FDG-PET or PET/CT, three (9.4%) studies [ 15 , 21 , 22 ] addressed 18 F-FDOPA, six (18.8%) studies [ 18 , 21 , 24 , 29 , 44 , 45 ] evaluated CT or MRI, two (6.3%) studies [ 14 , 41 ] assessed 68 Ga- SSAs, and one (3.1%) study [ 31 ] inquired into 111 In-pentetreotide. The remaining four (12.5%) studies [ 33 , 35 , 36 , 45 ] mixed 131 I-MIBG and 123 I-MIBG together, and all of them acquired planar imaging only.…”

MIBG scans in patients with stage 4 neuroblastoma reveal two metastatic patterns, one is associated with MYCN amplification and in MYCN-amplified tumours correlates with a better prognosis

“…In international guidelines skeletal uptake of MIBG is reported to be visible as focal or diffuse lesions [ 18 ], and the SIOPEN scoring method distinguishes between discrete foci and diffuse lesions [ 6 ]. In the literature, “focal” lesions are mostly reported as bone metastases [ 19 , 20 ] and “diffuse” lesions as bone marrow metastases [ 19 , 21 – 24 ]. As almost 95 % of patients with stage 4 neuroblastoma have bone marrow involvement at diagnosis, the nature of focal and diffuse lesions was not studied in our cohort.…”

Complicated appearance of an abdominal mass in the I-131 MIBG and Tc-99m bone scintigraphy of a patient with neuroblastoma: Figure 1

“…Combination of MIBG with bone scintigraphy is considered as the best method to detect dissemination of neuroblastoma. According to a study by Shah Syed et al 6 MIBG has been found to be superior to CT in identification of primary site and soft tissue metastasis but inferior to bone scintigraphy in bone metastasis. Same researchers have found the method reliable in showing bone marrow involvement.…”