Neuroblastoma with a solitary intraventricular brain metastasis visualized on I-123 MIBG scan

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.

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.

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.