Neuroblastoma with a Solitary Intraventricular Brain Metastasis Visualized on I‐123 MIBG Scan

BACKGROUND: Although metastatic skull lesions of neuroblastoma are not uncommon, brain involvement is infrequent and prompt diagnosis is of utmost importance in such cases. Previous studies have shown that Meta-Iodo-Benzyl-Guanidine (MIBG) scans were not always reliable in detecting central nervous system metastases, however most published reports referred to the Iodine-131 ((131)I)-MIBG scans. Herein, we report an intraventricular metastasis of neuroblastoma diagnosed using an Iodine-123 ((123)I)-MIBG scan, which is increasingly being used in clinical practice and reported as a more accurate method for detecting metastatic lesions. CASE DESCRIPTION: An unusual case of metastatic neuroblastoma to the left lateral ventricle of the brain is presented. Planar (123)I-MIBG scintigraphy showed faint tracer activity close to the midline without asymmetric extensions or abnormal activity in the skull bones. A subsequent brain MR scan revealed an enhancing mass within the left frontal horn consistent with a metastatic lesion. The patient underwent tumor resection with pathology showing neuroblastoma. CONCLUSIONS: Our case shows that (123) I-MIBG scintigraphy can be useful in detecting intraventricular brain metastases of neuroblastoma. Although the (123)I-MIBG scintigraphy has been reported to have a significantly superior sensitivity in monitoring asymptomatic patients with neuroblastoma compared with (131)I-MIBG scans, bone marrow histology, bone scan, CT, and urinary catecholamine levels, further studies may be necessary to evaluate its sensitivity in detecting brain lesions.